Part 2: (Almost) Complete guide to all Finnish noun declensions (Plurals)

19 min readAug 2, 2020

Just an irrelevant photo of Helsinki from the internet for the thumbnail. Photographed by Sergey Sigov

Before going further, read Part 1 here
Link:
https://medium.com/@heinrich.tsanov/complete-guide-to-all-finnish-noun-declensions-almost-6ebe18b144fc

Have you read it yet? Yes? Good. Before you read on, please be reminded that the footnotes help you to understand the full picture, when you have a clear mind. If you prefer to learn things by brute force and want to be lazy, then just ignore them, but I strongly recommend you to read them.

Please also check out the appendix about Finnish phonotactics if you are interested.

ENCOURAGEMENT: This article seems very long, but you will see the same patterns over and over again. You are also recommended to search for the stem endings and read this like a rule book. Once you know what you are doing, it is not that complicated. Finnish is completely learnable. Don’t give up.

Now continue reading.

T o recap and better summarise from part 1, a singular Finnish inflected noun (or adjective) form consists or 2(3) elements: word stem + (phonotactic linking infix)¹+ case ending. Then apply sound rules and gradation rules to it. Ta-da, there you go.

Example: All you need to know is the stem, as well as the partitive, genitive, illative, and lastly, nominative, then you will be able to derive all other forms from them, by applying sound rules and gradation rules.

To create the plural, it is easy for the nominative: just use the singular stem, then add -t. In other words, if you replace the final -n in the genitive singular form with -t, you will always (100% of the time) get the nominative plural form.

You should be familiar with the declension patterns after reading part 1, so I will not show the stem in the following examples

Nom. sg. | Gen. sg. | Nom. pl

However, you need to do more when you want to decline it into other cases. One more element is required: a plural infix. So, a Finnish inflected plural noun contains 3(4) elements: stem + plural infix + (phonotactic linking infix) + case ending. Then apply sound rules and gradation rules to it.

There are 3 plural infixes: -i-/-j-, -id- and -t-.

In most cases, you use -i-/-j-. You only use the other two for the genitive of certain noun classes. The genitive is confusing sometimes even for native speakers, so there are usually multiple possible forms, but only one of them is used the most. Read this for some enlightenment, if you understand some Finnish.

You get what I mean by “multiple” here? By the way, this word means “tear”, the liquid in your eyes while you learn Finnish. (Source: Wiktionary)

So, let’s begin with examples.

The gradation rules are a bit different from the usual ones³. Now consider all instances of a consonant before a diphthong that contains the plural infix -i- gradatable in closed syllables, unless I tell you not to.

Vowels

Stem ending -O / -U

Basically, the best case scenario is that you insert an -i-/-j- in the singular counterpart:

Nom. sg. || Gen. pl. | Part. pl. | Ill. pl. | All. pl.

peitto || peitto-j-en | peitto-j-a | peitto-i-hin | peito-i-lla blanket
näkö || näkö-j-en | näkö-j-ä | näkö-i-hin | näö-i-llä sight
katu || katu-j-en | katu-j-a | katu-i-hin | kadu-i-lla street
sänky || sänky-j-en | sänky-j-ä | sänky-i-hin | sängy-i-llä bed

The form -i- and the form -j- are most of the time the same entity⁴. It is written as -j- between vowels for orthographic reasons. Now you can easily decline any noun or adjective! (If they end with -O or -U.)

I have shown you the allative forms in this section just to give you examples of gradation before diphthongs containing the plural infix. The allative forms will be omitted from now on, and you should assume gradation takes place in every valid instance, unless I tell otherwise.

Stem ending -e (-Ce)

If the stem ending (not the nominative, check part 1 if confused) is -Ce, where C is none of the dental sounds l, r, n, s, then remove the final -e before -i-. For simplicity, singular stems are omitted here as you should be able to derive them yourself after reading part 1.

susi || sus-i-en | sus-i-a | sus-i-in wolf
siipi || siip-i-en | siip-i-ä | siip-i-in wing
jälki || jälk-i-en | jälk-i-ä | jälk-i-in trace
lohi || loh-i-en | loh-i-a | loh-i-in salmon

Stem ending -C(e) (dental)

What if C is one of the dental sounds l, r, n, s? You might as well ignore what I have said:

kieli || kiel-i-en | kiel-i-ä | kiel-i-in language
kuori || kuor-i-en | kuor-i-a | kuor-i-in shell
pieni || pien-i-en | pien-i-ä | pien-i-in small
lapsi || laps-i-en | laps-i-a | laps-i-in child

But you might also replace -i- with -t- in the genitive case:

kieli || kiel-t-en | kiel-i-ä | kiel-i-in language
kuori || kuor-t-en | kuor-i-a | kuor-i-in shell
pieni || pien-t-en | pien-i-ä | pien-i-in small
lapsi || las-t-en² | laps-i-a | laps-i-in child

It is often hard to tell which one to use; both forms are correct, but usually one of them is used more frequently. (As you learn Finnish long enough, you will realise that e.g. the form lasten is far more frequently used than lapsien, though both forms are correct.)

Stem ending -i

The short noun/adjectives (of exactly 2 syllables) with stem ending -i (NOT nominative, see Part 1) with changes the ending to -ei- in inflected plural forms in general, but -i- is used for genitive.

tili || til-i-en | til-ej-ä | til-ei-hin account
äiti || äit-i-en | äit-ej-ä | äit-ei-hin mother
laji || laj-i-en | laj-ej-a | laj-ei-hin sort, kind

The long noun/adjectives (of 3 or more syllables) with stem ending -i changes the ending to -ei- in inflected plural forms in general, but you can either use -i- or -ei- for genitive. All genitive forms of Finnish nouns and adjectives with -iden have an alternative form of -itten, but they are rarely used and are mainly poetic. They will be omitted after this section.

enkeli || enkel-i-en | enkel-ei-tä | enkel-ei-hin angel
……….. enkel-eid-en | enkel-ej-ä ………………
……….. enkel-eitt-en ……………………………..

paperi || paper-i-en | paper-ei-ta | paper-ei-hin paper
……….. paper-eid-en | paper-ej-a ………………
……….. paper-eitt-en ……………………………..

kaveri || kaver-i-en | kaver-ei-ta | kaver-ei-hin friend, pal, buddy, dude
……….. kaver-eid-en | kaver-ej-a ………………
……….. kaver-eitt-en ……………………………..

Stem ending -A

Phew.

A simplified summary of the general rule.

Unlike words of other stem endings, the tricky part of words of stem ending -A is that it sometimes gets removed, otherwise it becomes -O- , depending on the situation.

If the final -A is part of a grammatical suffix, then there are rules for each suffix. If you don’t know what that is, it’s okay, I will help you recognise some of them. We will talk about that later. Let’s start with the normal ones.

If the word ends with -ä, remove it.

päivä || päiv-i-en | päiv-i-ä | päiv-i-in day
kesä || kes-i-en | kes-i-ä | kes-i-in summer
perä || per-i-en | per-i-ä | per-i-in rear, back, aft
ystävä || ystäv-i-en | ystäv-i-ä | ystäv-i-in friend

If the word ends with -a, the first vowel letter of the word determines what to do.

If the first vowel letter is one of a, e, i, and the word consists of 2 syllables, then change the final -a to -o-.

kala || kalo-j-en | kalo-j-a | kalo-i-hin fish
rauha || rauho-j-en | rauho-j-a | rauho-i-hin peace
sika || siko-j-en | siko-j-a | siko-i-hin pig
hiekka || hiekko-j-en | hiekko-j-a | hiekko-i-hin sand
keikka || keikko-j-en | keikko-j-a | keikko-i-hin gig
keula || keulo-j-en | keulo-j-a | keulo-i-hin bow, prow
zeta || zeto-j-en | zeto-j-a | zeto-i-hin the letter Z

A word of 3 or more syllables, whose first vowel letter is one of a, e, i, if it DOES NOT end in -ea or -oa, also get the final -a changed to -o-, but they have slightly different case endings. As what I have said before, -iden can alternatively be -itten for poetic use.

energia || energio-id-en | energio-i-ta | energio-i-hin energy
hartia || hartio-id-en | hartio-i-ta | hartio-i-hin shoulder
tavara || tavaro-id-en | tavaro-i-ta | tavaro-i-hin goods

If the first vowel letter is one of o or u, then remove the final -a.

omena || omen-i-en | omen-i-a | omen-i-in apple
koira || koir-i-en | koir-i-a | koir-i-in dog
kukka || kukk-i-en | kukk-i-a | kukk-i-in flower
suoja || suoj-i-en | suoj-i-a | suoj-i-in shelter

Notable exception:
suola || suolo-j-en | suolo-j-a | suolo-i-hin salt

(Explanation⁵)

Words ending in -eA or -oa always get the final vowel removed in inflected plural forms, and they never trigger gradation (the “long-ending”)⁶. Words of this type always consist of 3 or more syllables.

oikea || oike-id-en | oike-i-ta | oike-i-si-in correct
pimeä || pime-id-en | pime-i-tä | pime-i-si-in dark
ainoa || aino-id-en | aino-i-ta | aino-i-si-in only, sole

The illative plural ending of this particular type of words can also be -ihin, but not all words with “long endings” are allowed to take -ihin.

To play safe, you should always use -isiin after “long endings” for an easier life.

Certain suffixes always get the final -A removed. Here is a non-exhaustive list of examples.

verbal noun suffix “-ing” -mA

tapahtuma || tapahtum-i-en | tapahtum-i-a | tapahtum-i-in event
sattuma || sattum-i-en | sattum-i-a | sattum-i-in chance, coincidence

verbal adjective “-ing” / noun adjectivising suffix “-ful, -y” -vA

mahtava || mahtav-i-en | mahtav-i-a | mahtav-i-in great, magnificent
lihava || lihav-i-en | lihav-i-a | lihav-i-in fat

noun adjectivising suffix “-ful, -y” -isA

kaikuisa || kaikuis-i-en | kaikuis-i-a | kaikuis-i-in reverberant
ehtoisa || ehtois-i-en | ehtois-i-a | ehtois-i-in generous

noun adjectivising suffix -rA

ankara || ankar-i-en | ankar-i-a | ankar-i-in harsh
ahkera || ahker-i-en | ahker-i-a | ahker-i-in industrious
avara || avar-i-en | avar-i-a | avar-i-in spacious

agent suffix “-er” -jA after all vowels except i

antaja || antaj-i-en | antaj-i-a | antaj-i-in giver
kääntäjä || kääntäj-i-en | kääntäj-i-ä | kääntäj-i-in translator

Certain suffixes always get the final -A changed to -O-. Here is a non-exhaustive list of examples.

agent suffix “-er” -jA after i

tekijä || tekijö-id-en | tekijö-i-tä | tekijö-i-hin author, maker, doer
kulkija || kulkijo-id-en | kulkijo-i-ta | kulkijo-i-hin traveller

suffix to form nouns of places, -lA

onnela || onnelo-id-en | onnelo-i-ta | onnelo-i-hin paradise
ruokala || ruokalo-id-en | ruokalo-i-ta | ruokalo-i-hin dining hall, canteen
myymälä || myymälö-id-en | myymälö-i-tä | myymälö-i-hin shop

suffix to form action nouns from verbs, which mostly describe sounds, -nA

kipinä || kipinö-id-en | kipinö-i-tä | kipinö-i-hin spark
loiskina || loiskino-id-en | loiskino-i-ta | loiskino-i-hin splash (sound)

It is quite impossible to list out all suffixes that inflect in a specific way. Just take it as a concept. You might be able to find other suffixes on your own.

Once again, there are always exceptional cases in natural languages. You should watch out for each of them.

Stem ending -VV

Monosyllabic nouns/adjectives ending with -V₁V₂ becomes -V₂i- when combined with the plural infix. Note that genitive takes -iden.

maa || ma-id-en | ma-i-ta | ma-i-hin land, soil, ground, country
suo || so-id-en | so-i-ta | so-i-hin swamp
tie || te-id-en | te-i-tä | te-i-hin road
yö || ö-id-en | ö-i-tä | ö-i-hin night

Nouns/adjectives that consist of 2 or more syllables and end with a long vowel always get the final vowel removed and changed to -i- in inflected plural forms, and they never trigger gradation (the “long-ending”).

vapaa || vapa-id-en | vapa-i-ta | vapa-i-si-in free
kaipuu || kaipu-id-en | kaipu-i-ta | kaipu-i-si-in longing
palttoo || paltto-id-en | paltto-i-ta | paltto-i-si-in overcoat
miljöö || miljö-id-en | miljö-i-tä | miljö-i-si-in milieu
filee || file-id-en | file-i-tä | file-i-si-in fillet

Some of the words of this type (NOT ALL) can also alternatively take -ihin, but to make sure you are correct, you should use -isiin. (I don’t even bother to tell you which ones can take -ihin. Google it yourself, lol.)

Consonants

Stem ending -Q (-eQ) (Nominative -e)

This type of nouns/adjective have a “long ending”.

To recap what we have gone through in Part 1, the -Q is an unwritten phonemic glottal stop that triggers gradation. It was historically a *-k or a *-h, which can further be gradated if a suffix is added behind it. This is why this type of words always have the “long ending”, as the diphthong that contains the plural infix, was in Proto-Finnic always 2 syllables instead of one⁷.

raide || raite-id-en | raite-i-ta | raite-i-si-in track
huone || huone-id-en | huone-i-ta | huone-i-si-in room
kyse || kyse-id-en | kyse-i-tä | kyse-i-si-in matter

The ending -isiin can also be -ihin in this class, but remember what I said, use -isiin for a “long ending”, whenever possible.

Stem ending -X and -T

These types of nouns/adjective have a “long ending”⁸.

rengas || renka-id-en | renka-i-ta | renka-i-si-in ring, tyre
kirves || kirve-id-en | kirve-i-tä | kirve-i-si-in axe
kaunis || kauni-id-en | kauni-i-ta | kauni-i-si-in beautiful
kevät || kevä-id-en | kevä-i-tä | kevä-i-si-in spring (season)
olut || olu-id-en | olu-i-ta | olu-i-si-in beer
lyhyt || lyhy-id-en | lyhy-i-tä | lyhy-i-si-in short

The ending -isiin can also be -ihin in these classes, but you know what I am going to say.

Stem ending -nUt (participle suffix)

If you should in part 1, the ending changes to -nee- when it is not the nominative, or when it is the nominative plural (in which case it is -neet). When it is in a non-nominative plural form, -nee- combines with plural infix -i- to get -nei-.
You should know that the ending -nUt looks different after certain verb stems (explanation here⁹).

kuollut || kuolle-id-en | kuolle-i-ta | kuolle-i-si-in dead
menehtynyt || menehtyne-id-en | menehtyne-i-tä | menehtyne-i-si-in passed away

Stem ending -(U)Ut (nominative -(U)Us)

Unparallel to the singular forms, the inflected plural forms of this type changes the stem ending to -(U)Uks.

vapaus || vapauks-i-en | vapauks-i-a | vapauks-i-in freedom
oikeus || oikeuks-i-en | oikeuks-i-a | oikeuks-i-in justice, right, law
terveys || terveyks-i-en | terveyks-i-ä | terveyks-i-in health
itsenäisyys || itsenäisyyks-i-en | itsenäisyyks-i-ä | itsenäisyyks-i-in independence
kansallisuus || kansallisuuks-i-en | kansallisuuks-i-a | kansallisuuks-i-in nationality

Stem ending -s (Nominative -nen)

ihminen || ihmis-t-en | ihmis-i-ä | ihmis-i-in person
hevonen || hevos-t-en | hevos-i-a | hevos-i-in horse
perhonen || perhos-t-en | perhos-i-a | perhos-i-in butterfly, moth

Pretty much the same as the stems ending with -C(e) with a dental C, except the -t- genitive is far more preferable than the one with -i-, even if both are correct.

Stem ending -nt

When the stem final -nt hit the plral infix -i-, it got palatalised and evolved into an -ns-.

neljäs || neljäns-i-en | neljäns-i-ä | neljäns-i-in 4th
tuhat || tuhans-i-en | tuhans-i-a | tuhans-i-in 1000

Stem ending -C

All other previously unmentioned stems with consonant ending falls into this category.

There are two subtypes of words in this category: As a rip-off of Kotus’ categorisation (which overcomplicates things too much by the way), let’s name them Type sisar and Type askel, in MY definition (Not Kotus’).

Usually you have to memorise the declension type of each word, but here is the (unhelpful) advice:
1. Does the nominative singular form end with -l, -n or -r? If not, it must be of Type sisar.

2. See if there are more than one nominative singular forms of the word. If there is an alternative form with an extra -e at the end, it is of Type askel. Otherwise it is of Type sisar.

Type sisar

Words of this type have 2 alternative forms of genitive plural. Don’t forget to apply rules of gradation and phonotactics.

sisar || sisar-t-en | sisar-i-a | sisar-i-in sister
…………sisar-i-en
tytär || tytär-t-en | tyttär-i-ä | tyttär-i-in daughter
…………tyttär-i-en
jäsen || jäsen-t-en | jäsen-i-ä | jäsen-i-in limb, member
………….jäsen-i-en
sävel || sävel-t-en | sävel-i-ä | sävel-i-in tone, note, tune
………….sävel-i-en
puhelin || puhelin-t-en | puhelim-i-a | puhelim-i-in telephone
……………..puhelim-i-en
avain || avain-t-en | avaim-i-a | avaim-i-in key
………….avaim-i-en
päätös || päätös-t-en | päätöks-i-ä | päätöks-i-in decision
……………päätöks-i-en
petos || petos-t-en | petoks-i-a | petoks-i-in treachery, treason, fraud
………… petoks-i-en
vaatimus || vaatimus-t-en | vaatimuks-i-a | vaatimuks-i-in demand
……………….vaatimuks-i-en
vallankumous || vallankumous-t-en | vallankumouks-i-a | vallankumouks-i-in revolution
………………………vallankumouks-i-en

Type askel

You can either treat words of this type as having a stem ending -eQ, or decline it like Type sisar.

Words like askel, kyynel, manner and penger have alternative forms askele, kyynele, mantere and penkere respectively, they fall into this Type askel.

As you already know how words of Type sisar decline, the following will only show -eQ declensions.

askel || askele-id-en | askele-i-ta | askele-i-si-in step
kyynel || kyynele-id-en | kyynele-i-tä | kyynele-i-si-in tear
manner || mantere-id-en | mantere-i-ta | mantere-i-si-in continent, mainland
penger || penkere-id-en | penkere-i-tä | penkere-i-si-in embankment, terrace

Appendix

Finnish phonotactics for consonants

https://medium.com/@heinrich.tsanov/appendix-phonotactic-rules-of-the-finnish-language-for-consonants-7044108a8553

Footnotes

This is the -e- (according to my model) in kielen/avoimen and -se- in Espooseen/koneeseen. See Class -C, -eQ and -VV in Part 1.
[Unnecessary information #1 for linguistic nerds] For words with the nominative forms ending in -Di in Class -C, where D is a dental sound l/r/n/s (examples include kieli, veri, pieni, vesi) , the stem ending was not actually a consonant. It was a Proto-Uralic -a, which reduced to a weaker vowel -ë [*ɤ] in Proto-Finnic. It merged with e in Finnish most of the time, while it further reduced to -i in word-final position. When it was between a dental (with a small number of non-dental exceptions) and a -T (a weak -t that disappears between vowels), it vanished. This explains why the partitive of siipi is siipeä and that of hiiri is hiirtä.
[/Unnecessary information #1 for linguistic nerds]
[Unnecessary information #2 for linguistic nerds]
Have you ever wondered what the purpose of -se- is? It is indeed a buffer. Just imagine this etymologically incorrect story: When ancient Finns tried to form illatives of nouns, they added illative case suffix -h#n to it. In many cases the -h- was too weak to be heard and it disappeared. So later Finns mostly realised -#n as the illative suffix. In layman’s terms, to make a noun or adjective illative, you lengthen the previous vowel and add -n. However, you can’t always lengthen a vowel, when the vowel is already long or a diphthong. You can’t make Espoo into *Espooon, so -se- is added in between, to become Espooseen. Unfortunately, all natural languages have exceptions. You can’t do the same thing to Hyvinkää, you have to say Hyvinkäähän, not *Hyvinkääseen. The excuse for this is that the nominative is a re-analysis of the inflected forms. The original unattested nominative form could have been *Hyvingäs. (You won’t use the illative form much anyway. You say Hyvinkäälle, the allative, when you mean “to Hyvinkää”, just like all place names derived from a river.)
[/Unnecessary information #2 for linguistic nerds]

2. Obviously you cannot say *lapsten. Finnish phonotactics disallows 3 consonants in a row, unless the first consonant in the cluster is a sonorant (That is why Finnish has words like torstai Thursday, ranska French, tanska Danish, melska fuss, myrsky storm, etc., amongst which are often Swedish/Germanic loans except the last two). Relatively recent loan words may violate phonotactic rules often. You may see words like hamstrata to hoard, a word taken quite directly from Swedish (att hamstra < German hamstern).

3. Many textbooks tell you that gradation only takes place before a monophthong (single vowel). This is merely a generalisation and a simplification. Diphthongs with -i is often the source of headache.

You can treat all diphthongs formed by the plural infix -i- as “short”, where gradation takes place, except for -ei, as it is variable and it depends on which class the word is in.

[Explanation] (you may omit this part for the moment)

Rule of thumb:
If the -i in a diphthong is a phoneme /j/, consider the the syllable short (gradation takes place). If the -i in a diphthong is a phoneme /i/, consider the syllable long (no gradation).

Phonotactically, when you add /i/ after a short vowel, you always end up with a diphthong in a what-you-see-is-what-you-get manner, which means -V + /i/ becomes -Vi, where Vi is a diphthong, unless V is i, then -i + /i/ is i (and it is no longer a diphthong).
-i + /i/ > -i
Otherwise
-V + /i/ > -Vi

I will simply call it the “long ending” in the rest of this article.

Examples:
anta- > antaisi (he/she/it) would give
raiteQ- > raiteilla on the tracks

However, /j/ is much more tricky.
-a + /j/ > -oi, -i
-ä +/j/ > -i, rarely -öi
-i + /j/ > -ei (nouns), -i (nouns and verbs)
-e + /j/ > -i
Otherwise
-V + /i/ > -Vi

Examples:
anta- > annoin I gave
laki- > laeissa in the laws

We will go over some of the examples in the main text.

[/Explanation]

4. It is the phoneme /j/, unless it is after a (current or historical) consonant, then it is /i/. See footnote #3.

5. Probably ancient Finns altered the declension pattern of the word to avoid confusion from the inflected plural forms of the word suoli intestines, which goes:
suoli || suol-i-en | suol-i-a | suol-i-in intestines

6. The sequence -eA or -oa is two short vowels, instead of a diphthong. So the plural infix is by principle a phonemically syllable-starting /i/ that disallows gradation (Finnish phonotactics forces it to be part of a diphthong phonetically though). See footnote #3 for more details.
As the diphthongs -ei- and -oi- here are considered “long” (See footnote #1), any attempt to lengthen a long vowel will result in the addition of a buffer infix -se-, which becomes -si- in the plural. Combining -si- and the illative -#n will give you -siin.

7. The *-k was weakened to *-g- [*ɣ], and the *-h remained unchanged, yet it was then weakened to null. Both consonants in the same position have vanished in modern Finnish, but they left their trace. When a noun/adjective ended with *-Cek / *-Ceh, they became *-Cegi- / *-Cehi-, then became -Cei- in modern Finnish. See why the -C- never undergoes gradation except for the nominative singular? The reason is simple: It was always in an open syllable, whenever it is not the nominative singular.

8. Similar to Footnote #7. It is that the *-s was weakened to *-h-, or the *-t was weakened to *-d-. Both disappeared in modern Finnish.

9. Assimilation takes place when the verb stem ends with a consonant. The initial n in -nUt is assimilated by -s-, -l-, -r-. The initial n in -nUt assimilates the final -T- in the verb stem.

Examples:
nousta (Stem: nous-) to rise
nous- + -nut > noussut risen

kuolla (Stem: kuol-) to die
kuol- + -nut > kuollut

purra (Stem: pur-) to bite
pur- + -nut > purrut

haluta (Stem: haluT-) to want
haluT- + -nut > halunnut