1   Introduction

The genitive stem is a very important stem of Finnish nominals. Most cases are formed by adding endings directly to it. This applies to the singular form of the genitive, accusative (long form), translative, inessive, elative, adessive, ablative, allative, abessive, and instructive, and the plural form of the nominative and accusative. A good knowledge of consonant gradation and vowel change i ~ e is of great use.

2   Formation

The formation of the genitive stem is very complicated. The following rules show, how the genitive stem is formed from the nominative stem. In the examples, the first form is the nominative stem or the nominative singular and the second one is the genitive stem with the genitive ending -n.

2.1 Words that end in a vowel

a) Words that do not undergo vowel change i ~ e

This group includes all the words that end in a, o, u, y, ä, and ö. This group also includes a small number words that end in e. Most words that end in e actually end in a relic consonant, and therefore they decline like words ending in a normal consonant (see chapter 2.2 a below). The only group of words that requires memorizing consists of words ending in i, because they can undergo the vowel change i ~ e. This group includes the words that do not undergo the change.

The genitive stem of these words is similar to the nominative stem, except for that the consonant gradation is applied to appropriate words.

Nominative	Genitive	Translation
koira	koira-n	dog
nalle	nalle-n	teddy bear
kiivi	kiivi-n	kiwi fruit
talo	talo-n	house
koulu	koulu-n	school
syy	syy-n	reason
kylä	kylä-n	village
yö	yö-n	night

If a word contains a consonant or a consonant cluster, which is affected by the consonant gradation, the genitive stem takes the weak grade.

Nominative	Genitive	Translation
silta	silla-n	bridge
vihko	viho-n	notebook

b) Words that undergo vowel change i ~ e

If a word undergoes the vowel change i ~ e, the genitive stem is formed by replacing the i by e.

Nominative	Genitive	Translation
kieli	kiele-n	language

A word may undergo both the vowel change i ~ e and the consonant gradation. In this case, the genitive stem takes the weak grade as well.

Nominative	Genitive	Translation
koipi	koive-n	leg
särki	särje-n	roach

Note especially words that end in -si and undergo the vowel change i ~ e. Because of a ancient change si ~ ti, these words still decline as if there were a t instead of the s. As t is a phoneme that is affected by the consonant gradation, the genitive stem, in addition, takes the weak grade. The following table shows all the possible inflectional types.

Nominative	Genitive	Translation
vesi	vede-n	water
kansi	kanne-n	lid
jälsi	jälle-n	cambium
virsi	virre-n	hymn

Exceptions!
The genitive stem of jousi, kusi, and kuusi is formed just by replacing i by e.

Nominative	Genitive	Translation
jousi	jouse-n	bow
kusi	kuse-n	piss
kuusi	kuuse-n	spruce

Exception!
The word veli requires an additional j in the genitive stem.

Nominative	Genitive	Translation
veli	velje-n	brother

Note!
The genitive stem of yksi and kaksi is formed by replacing ksi by hde.

Nominative	Genitive	Translation
yksi	yhde-n	one
kaksi	kahde-n	two

c) Comparative forms

The genitive stem of comparative forms is formed by replacing the comparative ending -mpi by mma. The change from mp to mm is caused by the consonant gradation.

Nominative	Genitive	Translation
suurempi	suuremma-n	bigger
isompi	isomma-n	bigger
kauniimpi	kauniimma-n	nicer

d) New loan words

The consonant gradation is not applied to some new loan words.

Nominative	Genitive	Translation
auto	auto-n	car

2.2 Words that end in a consonant

There are only five consonants (l, n, r, s, and t), which a Finnish word can end in. Anyway, loan words can end in any consonant. As case endings cannot usually be attached directly after a consonant, a space vowel e is traditionally used between the word and the ending. Nowadays this e has been sometimes assimilated by the preceeding vowel.

a) Words that end in a relic consonant

If a word ends in a relic consonant, the genitive stem is formed by adding another e to the nominative stem. A relic consonant is a letter, usually h or k, which has disappeared in the modern Finnish, but still affects the pronunciation. Nowadays, the last letter of these words is e. The consonant gradation is applied to appropriate words, and then the genitive stem takes the strong grade.

Nominative	Genitive	Translation
vene	venee-n	boat
koe	kokee-n	test
laite	laittee-n	device

b) Words that end in s

If a word ends in s, there are four ways of forming the genitive stem. It is quite difficult to conclude which way should be applied to a word, and therefore those below are quite ambiguous. More exact rules will be added later.

Type I

If a word has been derived from a verb, the genitive stem is usually formed by replacing the s by kse. These words usually end in -os/-ös or -us/-ys. This group also includes words that are not derivations.

Nominative	Genitive	Translation
varis	varikse-n	crow
hius	hiukse-n	hair
tulos	tulokse-n	result
kynnys	kynnykse-n	treshold
väärennös	väärennökse-n	forgery

Type II

If a word has been derived from a noun or an adjective, and it ends in -us/-ys, in front of which there is a vowel, the genitive stem is formed by replacing the s by de.

Nominative	Genitive	Translation
osuus	osuude-n	share, part
kauneus	kauneude-n	beauty
rakkaus	rakkaude-n	love
teollisuus	teollisuude-n	industry
hyvyys	hyvyyde-n	goodness

Type III

If a word is a number or a pronoun, which refers to a number, the genitive stem is formed by replacing the s by nne.

Nominative	Genitive	Translation
kolmas	kolmanne-n	the third
neljäs	neljänne-n	the fourth
tuhannes	tuhannenne-n	the thousandth
mones	monenne-n

Type IV

The genitive stem of other words is formed by omitting the s and doubling the last vowel. These words often end in -as (about 8 exceptions), -äs (about 2 exceptions), -es (about 11 exceptions), or -is (about 9 exceptions). Only one word of this type ends in -os. The consonant gradation is applied to appropriate words, and then the genitive stem takes the strong grade.

This type especially includes words that end in -ias (one exception), -kas, -las (two exceptions), -mas, -nas (three exceptions), -oas, -ras, -sas, -tas, -uas, and -vas. See the list of words that belong to this type. Anyway, the list does not include words ending in -ias and -kas.

Nominative	Genitive	Translation
karvas	karvaa-n	bitter
tehdas	tehtaa-n	factory
varvas	varpaa-n	toe
kiuas	kiukaa-n	sauna heater
kirves	kirvee-n	ax
tiivis	tiivii-n	compact
uros	uroo-n	male
räystäs	räystää-n	eaves

Complete list

Exceptions!
The word paras is irregular and it requires an additional h in the genitive stem. The word mies also declines irregularly, because the s changes to he in the genitive stem.

Nominative	Genitive	Translation
paras	parhaa-n	the best
mies	miehe-n	man

c) Words that end in n

If a word ends in n, the genitive stem is formed by replacing the n by me. The consonant gradation is applied to appropriate words, and then the genitive stem takes the strong grade. Words that end in -en, -nen, and -ton/-tön, and superlative forms ending in -in, decline in a different way and they will be discussed separately below.

Nominative	Genitive	Translation
avain	avaime-n	key
sydän	sydäme-n	heart
sadin	satime-n	trap
hapan	happame-n	sour
otin	ottime-n	handle

Exceptions!
There are two words, in which the n is replaced by ma/mä. The word hapan can also be declined regularly (see above).

Nominative	Genitive	Translation
hapan	happama-n	sour
lämmin	lämpimä-n	warm

If a word ends in -en, the genitive stem is formed by adding e to the nominative stem. The consonant gradation is applied to appropriate words, and then the genitive stem takes the strong grade.

Nominative	Genitive	Translation
ien	ikene-n	gum
joutsen	joutsene-n	swan
jäsen	jäsene-n	member, part
höyhen	höyhene-n	feather
hiven	hivene-n	small amount
tyven	tyvene-n	calm

If a word ends in -nen, the genitive stem is formed by replacing the nen by se.

Nominative	Genitive	Translation
hevonen	hevose-n	horse
ihminen	ihmise-n	person
puinen	puise-n	wooden

If a word ends in -ton/-tön, the genitive stem is formed by replacing the ton/tön by ttoma/ttömä. Note that the change from t to tt is caused by the consonant gradation.

Nominative	Genitive	Translation
mahdoton	mahdottoma-n	impossible
työtön	työttömä-n	unemployed

If a word is a superlative form and thus ends in -in, the genitive stem is formed by replacing the n by mma/mmä. This group also includes the word vasen 'left'.

Nominative	Genitive	Translation
suurin	suurimma-n	the biggest
kaunein	kauneimma-n	the nicest
märin	märimmä-n	the wettest
köyhin	köyhimmä-n	the poorest
vasen	vasemma-n	left

The genitive stem of the numbers from 7 to 10 and from 17 to 19 is formed by omitting the n.

Nominative	Genitive	Translation
seitsemän	seitsemä-n	seven
kahdeksan	kahdeksa-n	eight
yhdeksän	yhdeksä-n	nine
kymmenen	kymmenen-n	ten
seitsemäntoista	seitsemä-n-toista	seventeen
kahdeksantoista	kahdeksa-n-toista	eighteen
yhdeksäntoista	yhdeksä-n-toista	nineteen

d) Words that end in l

If a word ends in l, the genitive stem is formed by adding e to the nominative stem. The consonant gradation is applied to appropriate words, and then the genitive stem takes the strong grade. This group includes about ten words.

Nominative	Genitive	Translation
askel	askele-n	step
kannel	kantele-n	kantele
kyynel	kyynele-n	tear
sävel	sävele-n	note, melody
sammal	sammale-n	moss
ommel	ompele-n	stitch
taival	taipale-n	trip
nivel	nivele-n	joint
vemmel	vempele-n
petkel	petkele-n	chopper

e) Words that end in r

If a word ends in r, the genitive stem is formed by adding e to the nominative stem. The consonant gradation is applied to appropriate words, and then the genitive stem takes the strong grade.

Nominative	Genitive	Translation
tatar	tattare-n	knotweed (Polygonum)
tytär	tyttäre-n	daughter
sisar	sisare-n	sister

f) Words that end in t

If a word ends in -at/-ät, the genitive stem is formed by removing the t and doubling the last vowel. This group includes only one word.

Nominative	Genitive	Translation
kevät	kevää-n	spring

If a word is a number, the genitive stem is formed by replacing the t by nne. This group includes only one word.

Nominative	Genitive	Translation
tuhat	tuhanne-n	thousand

If a word ends in -ut/-yt, the genitive stem is formed by replacing the t by e, except for participles. This group includes about eleven words.

Nominative	Genitive	Translation
ohut	ohue-n	thin
olut	olue-n	beer
lyhyt	lyhye-n	short
neitsyt	neitsye-n	virgin
kätkyt	kätkye-n
airut	airue-n	harbinger
kevyt	kevye-n	light
ehyt	ehye-n	whole
tiehyt	tiehye-n	duct
pehmyt	pehmye-n	soft

If a word is the active voice of a past participle and thus ends in -ut/-yt, the genitive stem is formed by replacing the ut/yt by ee.

Nominative	Genitive	Translation
juossut	juossee-n	run
laulanut	laulanee-n	sung
syönyt	syönee-n	eaten
vienyt	vienee-n	taken

Note!
The word ainut has no genitive stem of its own, but instead you use that of the word ainoa 'only'.

Nominative	Genitive	Translation
ainut	ainoa-n	only

g) Loan words

The genitive stem of new loan words, which end in a consonant, is formed simply by adding a vowel i to the nominative stem. Foreign proper nouns belong to this group as well. This rule also applies to words that end in the consonants l, n, r, s, and t.

Nominative	Genitive	Translation
rock	rocki-n	rock music
radar	radari-n	radar
Internet	Interneti-n	Internet
Linux	Linuxi-n	Linux
Windows	Windowsi-n	Windows
New York	New Yorki-n	New York

3   Usage

The genitive stem is used to form the singular form of the genitive, accusative (long form), translative, inessive, elative, adessive, ablative, allative, abessive, and instructive, and also the plural form of the nominative and accusative. It is also used to form the partitive, essive and plural stem.

The following example shows, how case endings are attached to the genitive stem.

Case	Word	Translation
Nominative sg	jalka	the foot
Accusative sg (long)	jalan	the foot
Genitive sg	jalan	of the foot
Translative sg	jalaksi	becoming the foot
Inessive sg	jalassa	in the foot
Elative sg	jalasta	out of the foot
Adessive sg	jalalla	on the foot
Ablative sg	jalalta	from the foot
Allative sg	jalalle	onto the foot
Abessive sg	jalatta	without the foot
Instructive sg	jalan	by foot
Nominative pl	jalat	the feet
Accusative pl	jalat	the feet