Derivational infixes for verbs

[Linguaphile]

-ta- causative

EXAMPLES

imema 'to suck'
imetama 'to suckle' (cause to suck)

istuma 'to sit'
istutama 'to plant' (cause to "sit")

kasvama 'to grow'
kasvatama 'to raise, cultivate' (cause to grow)

kiikuma 'to swing' (intransitive)
kiigutama 'to swing' (transitive) (cause to swing)

kuluma 'to wear, depreciate'
kulutama 'to spend' (cause to be worn/depreciated)

kõrbema 'to be burnt'
kõrvetama 'to burn [something]' (cause to be burnt)

levima 'to spread, diffuse'
levitama 'to spread, distribute' (cause to spread)

olema 'to be'
oletama 'to assume, to suppose' (cause to "be")

põlema 'to burn, catch fire'
põletama 'to burn, incinerate' (cause to catch fire / burn)

sündima 'to be born'
sünnitama 'to give birth' (cause to be born)

tekkima 'to arise'
tekitama 'to give rise' (cause to arise)

tulema 'to come'
tuletama 'to derive' (to cause to come)

välkuma 'to flash'
välgutama 'to make flash' (cause to flash)

õppima 'to learn'
õpetama 'to teach' (cause to learn)

===========================

-t- causative

EXAMPLES

jooma 'to drink'
jootma 'to water [an animal], to give [someone] something to drink' (cause to drink)

jääma 'to remain, to stay'
jätma 'to leave' (cause to remain)

keema 'to boil' (intransitive)
keetma 'to boil, to make boil' (transitive; cause to boil)

saama 'to get'
saatma 'to send, to accompany, to transmit' (cause to get)

sööma 'to eat'
söötma 'to feed' (cause to eat)

võima 'to be able, can'
võitma 'to win, defeat' ("cause to be able"?)

[Linguaphile]

-skle- continuous, non-intensive

EXAMPLES (derived from verb forms)

istuma 'to sit'
istusklema 'to sit for a while' (to sit continuously in a non-intensive manner)

kõndima 'to walk'
kõnnisklema 'to amble' (to walk continuously in a non-intensive manner)

lamama 'to lie'
lamasklema 'to lounge, to sprawl' (to lie continuously in a non-intensive manner)

mõtlema 'to think'
mõtisklema 'to meditate' (to think continuously in a non-intensive manner)

olema 'to be'
olesklema 'to idle' (to "be" in a continuously non-intensive manner)

otsima 'to seek, to look for'
otsisklema 'to seek constantly' (to look for continuously)

tantsima 'to dance'
tantsisklema 'to waltz, to jump or move playfully' (to move continuously in a dance-like way)

tegema 'to do'
teesklema 'to pretend' (to "do" continuously in a non-intensive [non-real] manner)

ujuma 'to swim'
ujusklema 'to swim slowly back and forth' (to swim continuously in a non-intensive manner)

[Linguaphile]

-le- frequentative/continuative, aimless

EXAMPLES (derived from verbs)

arutama 'to discuss'
arutlema 'to debate, to deliberate' (to discuss back and forth, to discuss repeatedly)

hoidma 'to keep, to preserve'
hoidlema 'to protect' (to repeatedly or continuously keep)

hüppama 'to jump'
hüplema 'to hop, skip' (jump repeatedly and aimlessly)

keksima 'to hop'
kekslema 'to hop around' (hop repeatedly and aimlessly)

lendama 'to fly'
lendlema 'to flit around' (fly repeatedly [back and forth or in stops and starts] and aimlessly)

näitama 'to show''
näitlema 'to act [i.e. in a theater]' (to "show repeatedly or continuously")

ostma 'to buy'
ostlema 'to shop' (to buy continuously)

peksma 'to beat'
pekslema 'to pound' (beat repeatedly or continuously)

pöörama 'to turn'
pöörlema 'to rotate' (turn repeatedly)

vaatama 'to watch'
vaatlema 'to look around, observe' (watch "aimlessly")

võitma 'to defeat'
võitlema 'to struggle, contend, fight' (to repeatedly and so far unsuccessfully [try to] defeat

==========

EXAMPLES (derived from nouns)

kaks (gen. kahe, part. kaht) 'two'
kahtlema 'to doubt'

kaup 'merchandise, goods'
kauplema 'to trade in, to deal in, to haggle'

mõte 'thought'
mõtlema 'to think'

retk 'trip, expedition'
retklema 'to go on a trip, to journey'

ring 'circle, ring, lap'
ringlema 'to circulate, to go around'

suhe (gen. suhte) 'relationship'
suhtlema 'to socialize, communicate'

[Linguaphile]

-tse- frequentative, gradual or prolonged

EXAMPLES (derived from verb forms)

armastama 'to love'
armatsema 'to be in a romantic or sexual relationship with, to flirt with' (to "love" frequently over a prolonged time)

elama 'to live'
elutsema 'to dwell in, to inhabit, to hang out in' (to live in frequently over a prolonged time)*

hoolima 'to care, to care about, to pay attention to'
hoolitsema 'to take care of, to look after' (to care about frequently over a prolonged time)

lärmama 'to make noise'
lärmitsema 'to clamour' (to make noise over a prolonged time)*

nokkima 'to peck'
nokitsema 'to tinker, to work on' (to "peck" frequently and gradually; figurative)

tegema 'to do'
tegutsema 'to act, to engage in' (to do frequently and gradually or over a prolonged time)

*Given the vowels that are used in the stem, it's more likely that some of the forms I've listed as derived from verbs are originally derived from the noun forms (elu, lärm(i), etc) rather than directly from the non-infixed verb, but I've listed them with the verbs in order to show the contrast in meaning between the verb form with -tse- and the verb form without -tse-.

=========

EXAMPLES (derived from nouns)

elu 'life'
elutsema 'to dwell in, to inhabit, to hang out in' (to live in frequently over a prolonged time)*

hale 'pitiful, pitiable, dismal'
haletsema 'to pity'

hääl 'voice, sound'
häälitsema 'to sound, to voice'

leek 'flame, fire, blaze'
leegitsema 'to blaze, to go up in flames'

leht 'leaf, page, sheet'
lehitsema 'to leaf through, to page through, to flick through'

lärm 'noise, ruckus'
lärmitsema 'to clamour' (to make noise over a prolonged time)*

maru 'storm'
marutsema 'to rage'

mure 'worry, concern, anxiety'
muretsema 'to worry; to take care of [someone]; to obtain'

õis 'flower'
õitsema 'to blossom, to bloom'

Also many loanword nouns have verbs formed this way (many of the verbs have a despective connotation):

EXAMPLES (derived from loaned nouns)

bürokraat 'bureaucrat'
bürokraaditsema 'to be bureaucratic'

demagoogia 'demagoguery, demagogy'
demagoogitsema 'to use demagoguery'

fraas 'phrase'
fraasitsema 'to phrase'

huligaan 'hooligan, hoodlum'
huligaanitsema 'to behave like a hooligan'

liberaal 'liberal'
liberaalitsema 'to show excessive tolerance'

literatuur 'literature'
literatuuritsema 'to express in an excessively literary way'

=========

EXAMPLES (derived from adjectives)

ahne 'greedy'
ahnitsema 'to take for oneself' (greedily)

hell 'tender, gentle'
hellutsema 'to be gentle, to be delicate'

morn 'gloomy, dour, morose'
mornitsema 'to be gloomy'

ülbe 'arrogant'
ülbitsema 'to act arrogantly, to speak arrogantly, to dis'

[Linguaphile]

-nda- causative, augmentative
Note: when derived from adjectives, generally has an augmentative-comparative meaning, i.e. "to make more [adjective]"

EXAMPLES (from adjectives and adverbs)

halb (halv-) 'bad'
halvendama 'to worsen, to exacerbate'

haljas (of plants) 'green'; (of metal) 'shiny'; (of liquid) 'clear'
haljendama 'to become verdant, to become [more] green'

hall 'grey'
hallendama 'to be grey, to appear grey'

harva 'seldom, rarely'
harvendama 'to thin' (to make more seldom or rare)

kerge 'light, easy'
kergendama 'to mitigate, to ease, to relieve' (to make easier)

kiire 'fast, quick'
kiirendama 'to accelerate, to quicken, to expedite, to speed up' (to make faster)

paras 'suitable, proper, fitting'
parandama 'to repair, to fix, to improve' (to make [more] suitable)

peen 'fine'
peenendama 'to refine, to make finer'

soe (sooja) 'warm'
soojendama 'to warm' (to make warmer)

========

-nda- factative
note: the connection between the noun and the verb is often fairly opaque due to semantic shifts over time

EXAMPLES (from nouns)

haru 'branch'
arendama 'to develop'

hind 'price'
hindama 'to evaluate, to assess, to price'

kaev 'well'
kaevandama 'to mine, to quarry'

kesk 'center'
keskendama 'to concentrate, to centralize, to focus'

täht (tähe-) 'star'
tähendama 'to signify, to mean'

väli 'field'
väljendama 'to express'

üks (ühe-) 'one'
ühendama 'to unify, to unite, to combine' (to make "one")

[Linguaphile]

-rda- factative, despective

EXAMPLES (from verbs)

kaapama 'to snatch, to grab, to scrape'
kaaperdama 'to hijack'

kompama 'to feel'
komberdama 'to stumble, to blunder along'

kööpama 'to limp'
kööberdama 'to hobble, to limp along'

=============

EXAMPLES (from nouns)

käpp 'paw'
käperdama 'to paw, to feel up'

sopp 'muck'
soperdama 'to mess, to muck, to fumble'

upp crouching position
ukerdama to plod along, clamber, move in a crouch-like position (earlier form uperdama)

=============

EXAMPLES (from adjectives)

jõnk abrupt, coarse, gruff
jõngerdama to move jerkily

lõhva awkward, clumsy
lõhverdama to behave awkwardly, to be boorish

==============

Note that there are also a large number of "-rdama" verbs which do not have the -rda- infix; the infix is actually -da- (a variation of -ta-), following a stem that ends with -r:

EXAMPLES

avar spacious, roomy
avardama to widen, to broaden, to amplify

hämar dim, dusky
hämardama to dim, to obfuscate

klamber clamp, clip, stample
klammerdama to staple, to clip

kähar curl, curly
kähardama to frizzle

vasar hammer
vasardama to hammer

veider strange, weird, eccenetric
veiderdama to clown around

=========--

There are also some onomatopoeic or semi-onomatopoeic verbs ending with -rdama, for which no source word exists (or remains) that I am aware of; they may be simply formed from onomatopoeia plus the infix:

EXAMPLES

ähvardama to threaten

jahmerdama to fuss about

puperdama to flutter

[Linguaphile]

-u- reflexive, intransitive
note: can be combined with other infixes, such as -ta-, -sta-, -nda-, etc. (where they become -tu-, -stu-, -ndu- and so on).

EXAMPLES

alandama 'to humiliate, to mortify'
alanduma 'to deign to, to demean oneself'

aurustama 'to vaporize (transitive)'
aurustuma 'to evaporate, to vaporize (intransitive)'

etendama 'to enact, to put on a show'
etenduma 'to be shown'

hoidma 'to hold, to carry'
hoiduma 'to avoid, to refrain'

kaevama 'to dig'
kaevuma 'to burrow (to dig oneself into)'

käivitama 'to start [something], to activate, to set into motion'
käivituma to start [oneself], to be activated, to be set into motion'

leidma 'to find'
leiduma 'to be found'

lülitama 'to switch on, to turn on' (transitive)
lülituma 'to switch on, to turn on' (intransitive)'

tundma 'to feel, to know'
tunduma 'to feel like, to appear'

tõmbama 'to drag, to pull'
tõmbuma 'to withdraw' (to drag/pull oneself)

===========

-du- reflexive
variant of -u- when the stem has a long vowel or dipthong followed by -l, -n, or -r.

EXAMPLES

haarama 'to grasp, to grab, to grip'
haarduma 'to mesh, to engage'

häälima 'to enunciate, to sound out'
häälduma 'to be voiced, to be pronounced'

juur 'root'
juurduma 'to entrench, to take root' (note also change in meaning: it is not "to uproot oneself")

keelama 'to forbid'
keelduma 'to refuse, to abstain'

kuulma 'to hear'
kuulduma 'to be heard, to be talked about'

painama 'to afflict, to harass, to haunt, to oppress'; dialect: 'to bend' (transitive)
painduma 'to bend, to flex' (intransitive)

veenma 'to persuade, convince'
veenduma 'to make certain, to ascertain' (to convince oneself)

[Linguaphile]

-bu-reflexive, intransitive
variant of -u- when a monosyllabic stem ends with a long back vowel or diphthong.

EXAMPLES

jooma 'to drink'
joobuma 'to be drunk'

looma 'to create'
loobuma 'to abandon, to relinquish'

maa 'land'
maabuma 'to land, to disembark'

saama 'to get, to receive'
saabuma 'to arrive'

suu 'mouth'
suubuma 'to flow into, to debouch'

=====================

-bi- reflexive, intransitive
variant of -u- when a monosyllabic stem ends with a long front vowel or diphthong.

EXAMPLES

käima 'to go'
käibima 'to pass, to circulate'

müüma to sell [transitive]
müübima to sell [intransitive]

sööma 'to eat'
sööbima 'to eat into'

viimane 'last'
viibima 'to stay'

öö 'night'
ööbima 'to spend the night'

Note: both of these infixes are added to either nouns or verbs; they tend to involve historical semantic shifts (which sometimes obscure the relationship between them) and are nonproductive.

[Linguaphile]

-ne- translative, gradual

EXAMPLES (from verbs)

hävima 'to be ruined; to perish; to be destroyed'
hävinema 'to go to ruin; to perish gradually; to be slowly destroyed'

levima 'to spread, to propagate, to be distributed'
levinema 'to gradually spread, to permeate''

olema 'to be'
olenema 'to depend on, to be conditioned by'

rippuma 'to hang, to be suspended'
ripnema 'to hang loosely, to dangle, to sag'

seisma 'to stand, to be upright'
seisnema 'to consist of'

sobima 'to fit, to suit'
sobinema 'to start to fit; to match'

sulama 'to melt'
sulanema 'to melt gradually'

tilkuma 'to drip, to drop, to leak'
tilknema 'to hang as a drip, to hang in drops; to drip down from'

tulema 'to come'
tulenema 'to originate, to derive'

=========

EXAMPLES (from adjectives and adverbs)

eel 'ahead'
eelnema 'to proceed'

halb 'bad'
halvenema 'to deteriorate, to worsen, to decline'

haige 'sick, ill'
haigenema 'to grow sicker'

kaasa 'with'
kaasnema 'to accompany'

koos 'together'
koosnema 'to consist of, to be composed of'

noor 'young'
noorenema 'to rejuvenate, to become younger'

paks 'thick, fat'
paksenema 'to become thicker, to become fatter'

palju 'much, a lot'
paljunema 'to procreate, to multiply, to reproduce'

pime 'dark, blind'
pimenema 'to darken'

terav 'sharp'
teravnema 'to sharpen'

vana 'old'
vananema 'to age, to grow old'

vähe 'small, little, few'
vähenema 'to diminish, to decrease'

=========

EXAMPLES (from nouns)

jagu 'allotment, share, portion'
jagunema 'to divide, to split'

janu 'thirst'
janunema 'to be thirsty; to be thirsty for, to thirst after'

kivi 'rock; stone'
kivinema 'to petrify; to become petrified'

põhi 'bottom, base'
põhinema 'to be founded, to be based on; to rest on'

rida 'row'
ridanema 'to be in a row'

võlg 'debt'
võlgnema 'to owe; to be indebted to'

[Naava]

These are so cool! Thanks for making the lists.

I'm once again comparing these to Finnish, and I thought I'd share my thoughts in case anyone else is interested. (I'll use the MA infinitive for Finnish verbs too.)

-ta- & -t- causative
This one is pretty much the same as in Finnish, but I thought it's interesting how Estonian has two forms (-ta- and -t-) while Finnish has only one (-ttA-):

(Estonian - Finnish)
istuma - istuma 'to sit'
istutama - istuttama 'to plant' (cause to "sit")

jooma - juoma 'to drink'
jootma - juottama 'to water [an animal], to give [someone] something to drink' (cause to drink)

jääma - jäämä 'to remain, to stay'
jätma - jättämä 'to leave' (cause to remain)

-le- frequentative/continuative, aimless

olema 'to be'
olesklema 'to idle' (to "be" in a continuously non-intensive manner)

This reminded me... Did you know that you won't get a residence permit here? Instead, you'll be granted oleskelulupa, or a 'permission to be idle'...

hoidma 'to keep, to preserve'
hoidlema 'to protect' (to repeatedly or continuously keep)

A funny false friend here:
hoitama 'to nurse, to care; to take care of; to finish, to square away'
hoitelema (slang) 'to have sex with'; also hoidella (pois) päiviltä 'to kill' (but hoitelema also has a more innocent meaning of 'to take care of something, to do some task (continously and/or indifferently)')

-tse- frequentative, gradual or prolonged

This one exists in Finnish (e.g. häiritsemä 'to disturb', palkitsema 'to reward) but not for any of the words you listed here! That's really weird because all the other groups have at least a few words that I can recognise.

I'm especially frustrated with these two:
ahne - ahne 'greedy'
ahnitsema - ahnehtima 'to take for oneself' (greedily)

hell - hellä 'tender, gentle'
hellutsema - hellimä 'to be gentle, to be delicate'

The meanings are the same, the root is the same, but the derivational suffix is not!

harva 'seldom, rarely'
harvendama 'to thin' (to make more seldom or rare)

Finnish harventama can also mean 'to remove some plants or parts thereof in order to improve the growth of those remaining'. Does Estonian have this too?

paras 'suitable, proper, fitting'
parandama 'to repair, to fix, to improve' (to make [more] suitable)

Are you sure the stem is paras and not (Proto-Finnic) para ('good, healthy, suitable')?

täht (tähe-) 'star'
tähendama 'to signify, to mean'

Thanks to this, I finally realised why tähendama has always sounded so familiar. There's the verb tähdentämä ('to emphasize, highlight'), which also comes from star and has the same suffix as in Estonian, but I never connected the dots because the meanings of tähendama, tähdentämä and täht(i) are so different...

Another false friend:

hoidma 'to hold, to carry'
hoiduma 'to avoid, to refrain'

hoitama 'to nurse, to care; to take care of; to finish, to square away'
hoituma 'to be fixed, to happen in an effortless manner'

-du- reflexive
variant of -u- when the stem has a long vowel or dipthong followed by -l, -n, or -r.

I thought this was interesting because that variant doesn't exist in Finnish:

kuulma - kuulema 'to hear'
kuulduma - kuuluma 'to be heard, to be talked about'

painama - painama 'to afflict, to harass, to haunt, to oppress'; dialect: 'to bend' (transitive) / 'to press, to weigh, to strain, to cause anxiety/concern'
painduma - painuma 'to bend, to flex' (intransitive) / 'to sink, to sag, to droop, to fall, to descend'

juurima 'to uproot, to pull up by the root'
juurduma 'to entrench, to take root' (note also change in meaning: it is not "to uproot oneself")

This one is interesting because in Finnish, the stem of juurtuma 'to take root' is juurtama '(figuratively) to have its roots in (of phenomena, opinions etc.)' and not juurima 'to uproot, root up, root (to tear up by the roots)'. Similarly, ääntymä 'to be pronounced, be enunciated, be articulated' is derived from ääntämä 'to pronounce, enunciate, articulate', unlike Estonian häälima vs häälduma.

-bu-reflexive, intransitive & -bi- reflexive, intransitive
Nobody asked, but apparently these come from an old variant of the suffix -v (as in olema > olev) and -U, which has become -u or -i in Estonian. (According to the old rule about consonant gradation in suffixes, you used the weak form -vA in unstressed syllables, and -pA in stressed syllables. Cf. Finnish käypä ('acceptable, decent'; from käydä/käima), juopa ('gulf, gap'; from juoda/jooma), syöpä ('cancer', from syödä/sööma, voipa ('being', in compounds; e.g. kaikkivoipa 'omnipotent', from voida/võima.)

Anyway, this one caught my attention:

viima - viemä 'to lead to, to take'
viibima - viipymä 'to stay'

It's weird Finnish has two different stems there (vie- and vii-). Are you sure viibima comes from viima? Wiktionary wasn't very helpful this time, but it seems that viima and viemä come from Proto-Finnic *veedäk (and Proto-Uralic *wixe-), whereas viipymä has the same root as in Proto-Finno-Ugric *wiŋe.

-ne- translative, gradual
I think this one is also interesting! As far as I can tell, we don't have it in Finnish except with adjectives: there are pairs like halpa - halpenema, nuori - nuorenema, paksu - paksunema, pimeä - pimenemä, vanha - vanhenema, but not anything like sulama - sulanema or kivi - kivinema in Estonian. (There is a word for 'to petrify' that is derived from kivi, but it's done with -ttAA + U: kivettyä or kivettymä.)

[Linguaphile]

I'm once again comparing these to Finnish, and I thought I'd share my thoughts in case anyone else is interested.

Cool, thanks!

-le- frequentative/continuative, aimless

olema 'to be'
olesklema 'to idle' (to "be" in a continuously non-intensive manner)

This reminded me... Did you know that you won't get a residence permit here? Instead, you'll be granted oleskelulupa, or a 'permission to be idle'...

I'm especially frustrated with these two:
ahne - ahne 'greedy'
ahnitsema - ahnehtima 'to take for oneself' (greedily)

hell - hellä 'tender, gentle'
hellutsema - hellimä 'to be gentle, to be delicate'

The meanings are the same, the root is the same, but the derivational suffix is not!

I believe this was done this way by Estonians just to see if they could mess with the Finns. I'm glad to see it worked.
No but seriously, Estonian does have hellima 'to be gentle,to be delicate, to be affectionate towards'.

harva 'seldom, rarely'
harvendama 'to thin' (to make more seldom or rare)

Finnish harventama can also mean 'to remove some plants or parts thereof in order to improve the growth of those remaining'. Does Estonian have this too?

Yes. In English "to thin" covers this as well.

paras 'suitable, proper, fitting'
parandama 'to repair, to fix, to improve' (to make [more] suitable)

Are you sure the stem is paras and not (Proto-Finnic) para ('good, healthy, suitable')?

Yes, it is para, but in Estonian it is not a word on its own. The closest full word I could come up with is paras. (Unlike some of my other lists, this thread is basically just comparing wordforms in modern Estonian, so I haven't listed etymological histories or included proto-forms. Although to be honest it's more difficult to avoid that than I realized it would be, because many of the infixed words are very old, and the infixes were added precisely to those proto-forms, not to the modern nouns/verbs/adjectives etc. So this leads me to use words like paras for parandama even though the root they share is actually the non-existent (in modern Estonian) word para.

täht (tähe-) 'star'
tähendama 'to signify, to mean'

Thanks to this, I finally realised why tähendama has always sounded so familiar. There's the verb tähdentämä ('to emphasize, highlight'), which also comes from star and has the same suffix as in Estonian, but I never connected the dots because the meanings of tähendama, tähdentämä and täht(i) are so different...

Yeah, that one is really cool. There is also täheldama and so on. It seems like there must be some way of getting a glimpse into an older understanding of the meaning(s) of *tähti, maybe a bit different than our own understanding of "star", by studying all of the words that were derived from it. Maybe some are metaphorical?

juurima 'to uproot, to pull up by the root'
juurduma 'to entrench, to take root' (note also change in meaning: it is not "to uproot oneself")

This one is interesting because in Finnish, the stem of juurtuma 'to take root' is juurtama '(figuratively) to have its roots in (of phenomena, opinions etc.)' and not juurima 'to uproot, root up, root (to tear up by the roots)'. Similarly, ääntymä 'to be pronounced, be enunciated, be articulated' is derived from ääntämä 'to pronounce, enunciate, articulate', unlike Estonian häälima vs häälduma.

Yeah, again, I was mainly listing words that had similar forms, not necessarily their true etymological roots. [no pun intended with 'roots', there, haha]. Maybe I should have listed it with the nouns and the root juur but I'm basically just looking at it from the perspective of similar verbs that different by infixes. (Ideally, I would have only listed verbs in this thread, but of course not all of the roots have a non-infixed verb, so it doesn't work.)
Anyway, if you were interested, Estonian does not have any juurt- verbs but does have juurutama 'to introduce, to bring in'.

Anyway, this one caught my attention:

viima - viemä 'to lead to, to take'
viibima - viipymä 'to stay'

It's weird Finnish has two different stems there (vie- and vii-). Are you sure viibima comes from viima?

Nope, not sure. I just assumed, wrongly. Good catch!

[edit: but then there is this which is one of the sites I consulted when making the list:
-bu-, -bi- liituvad ühesilbilisele pika vokaali või diftongiga lõppevale tüvele. Eesvokaalsetele tüvedele liitub -bi-, nt vii/bi/ma, käibima, sööbima, ööbima, müübima (erand: hääbuma), tagavokaalsetele -bu-, nt maa/bu/ma, joobuma, loobuma.
I guess that mislead me. It is still the -bi- inflix, but apparently not added to viima as I assumed, instead added to the same stem that is used in the word viimane, which is interesting because... where did the m in viimane come from? Or where did the m that is missing from the stem in viibima go? Apparently the proto-Finno-Ugric form was *wiŋe, so I guess the ŋ became m in viimane and got dropped from viibima?

[Linguaphile]

-ata- momentary action, one-time event (often sudden)
frequently formed from onomatopoeic stems

EXAMPLES

ehmuma 'to be startled'
ehmatama 'to frighten, spook, startle'

hüüdma 'to shout'
hüüatama 'to shout once, to call out'

kolksama 'to crash, to clash, to knock together'
kolksatama 'to crash once, to clash once, to knock together one time'

kopsama 'to knock'
kopsatama 'to knock suddenly; to rap once'

kriiksuma 'to creak'
kriiksatama 'to creak once (suddenly), to let out a creak'

laksama 'to smack, to slap, to spank'
laksatama 'to smack once, to slap once, to flap once'

loksuma 'to splash; to slosh; to cluck'
loksatama 'to splash once; to cluck once'

lonksama 'to toss down, to take a swig'
lonksatama 'to go down in one gulp'

naerma 'to laugh'
naeratama 'to smile'

norskama 'to snore'
norsatama 'to snort once'

nuuksuma 'to sob, to whimper'
nuuksatama 'to let out a sob, to sob once'

oigama 'to moan, to groan'
oiatama 'to moan once, to utter a groan'

seiskama 'to stop'
seisatama 'to stop short, to come to a halt'

============

-ahta- momentary action, one-time event
(variation of -ata-)

EXAMPLES

helama 'to ring, to sound'
helahtama (=helatama) 'to ring suddenly for a moment'

hirnuma 'to neigh, to whinny'
hirnahtama (=hirnatama) 'to neigh once, to whinny once'

karjuma 'to clamor, to scream'
karjahtama (=karjatama) 'to give a cry'

kiljuma 'to shriek, to scream'
kiljahtama (=kiljatama) 'to give a shriek, to scream once'

kõmama 'to boom, to rumble, to ring, to resound'
kõmahtama (=kõmatama) 'to bang, to crash'

liikuma 'to move'
liigahtama (=liigatama) 'to stir (once); to jerk'

urama 'to growl, to snarl, to grumble'
urahtama (=uratama) 'to grunt, to snarl once, to give a growl'

[Linguaphile]

-sta- causative (means or result)

EXAMPLES (from nouns)

arve 'account, record'
arvestama 'to take into account, to consider'

au 'honor'
austama 'to honor'

aur 'steam, vapor'
aurustama 'to vaporize, to evaporate'

higi 'sweat'
higistama 'to sweat, to perspire'

kaja 'echo'
kajastama 'to echo, to reverberate, to reflect'

kild 'fragment, shard'
killustama 'to fragment, to splinter'

küla 'village'
külastama 'to visit'

relv 'weapon'
relvastama 'to arm, to supply with weapons'

turv 'security, defense'
tuvastama 'to ascertain, to identify, to establish' (Yes, no 'r'! It was originally turvastama but changed due to a misspelling.)

viha 'anger'
vihastama 'to become angry'

=========

EXAMPLES (from adjectives)

kurb 'sad'
kurvastama 'to grieve, to regret'

nüri 'blunt, dull'
nüristama 'to dull, to deaden'

pruun 'brown'
pruunistama 'to brown, to sautee'

sama 'same'
samastama 'to identify with'

vaba 'free'
vabastama 'to liberate'

========

WIth some stems, the -ta-/-da- and -sta- forms of the verb have different meanings; with others, they are synonyms.

EXAMPLES (different meanings)

asutama 'to establish'
asustama 'to colonize, to inhabit'

suhkurdama 'to cover with sugar'
sukhrustama 'to make into sugar, to candy, to make like sugar'
(also note: the -da- form attaches to the nominative stem, the -sta- form attaches to the genitive stem.)

tolmutama 'go cover with dust, to dust'
tolmustama 'to become dust, to turn to dust'


EXAMPLES (same meaning)

lõunatama 'to have lunch, to dine'
lõunastama 'to have lunch, to dine'

mürgitama 'to poison, to intoxicate'
mürgistama 'to poison, to intoxicate'

mõjutama 'to influence, to impose'
mõjustama 'to influence, to impose'