Most Turkish suffixes start with a vowel, and many Turkish words end in one. When they meet, Turkish does not allow the two vowels to sit side by side: it slips a consonant between them. These consonants are the buffer letters (kaynaştırma harfleri): y, ş, s, n.
Memory trick: Yaşasın! (“Hooray!” / “Long live!”) contains all four: YaŞaSıN.
The key point: the suffix decides which buffer appears, not the word. The same word araba (car) takes three different buffers with three different suffixes:
| Suffix | Buffer | Result | Meaning |
|---|---|---|---|
| accusative -ı | y | arabayı | the car (as object) |
| possessive -ı | s | arabası | his/her car |
| genitive -ın | n | arabanın | of the car |
When the word ends in a consonant, no buffer is needed: ev gives evi, evi, evin.
Y: the default buffer
Y is by far the most common. It appears before vowel-initial case endings and before many verb and copula suffixes.
With case endings
| Word | + accusative | + dative | + “with” (ile) |
|---|---|---|---|
| kedi (cat) | kediyi | kediye | kediyle |
| araba (car) | arabayı | arabaya | arabayla |
| kutu (box) | kutuyu | kutuya | kutuyla |
| ütü (iron) | ütüyü | ütüye | ütüyle |
See the accusative and dative pages for when to use these cases.
With verb suffixes
Many verb suffixes start with a vowel, so vowel-final stems take y:
- bekle- + -ecek → bekleyecek (will wait) — future tense
- oku- + -abil- → okuyabilir (can read) — ability
- anla- + -alım → anlayalım (let’s understand)
- söyle- + -ince → söyleyince (when he said)
With “to be” endings
After a vowel-final noun or adjective, the personal “to be” endings take y (see personal pronouns and “to be”):
- Öğrenciyim. — I’m a student.
- Hastayız. — We are ill.
- Dün evde değildim, Ankara’daydım. — Yesterday I wasn’t at home, I was in Ankara.
S: only for the third-person possessive
S has one job: it joins the third-person possessive -ı/-i/-u/-ü (his, her, its) to a vowel-final noun.
| Word | His/her/its | Meaning |
|---|---|---|
| araba | arabası | his car |
| anne | annesi | her mother |
| kahve | kahvesi | his coffee |
| oda | odası | her room |
| kapı | kapısı | its door |
You will meet it constantly in compound nouns: Türk kahvesi (Turkish coffee), ev kapısı (front door), portakal suyu (orange juice). The possessive suffixes guide covers the whole set.
N: genitive, pronouns and “pronominal n”
N appears in three places.
1. The genitive after a vowel
- kapı → kapının (of the door)
- anne → annenin (the mother’s)
- Ayşe → Ayşe’nin (Ayşe’s)
See the genitive case.
2. After o, bu, şu
The pronouns o, bu, şu add n before every case ending and before the plural:
| Base | Accusative | Dative | Locative | Ablative | Plural |
|---|---|---|---|---|---|
| o | onu | ona | onda | ondan | onlar |
| bu | bunu | buna | bunda | bundan | bunlar |
| şu | şunu | şuna | şunda | şundan | şunlar |
More in demonstrative pronouns.
3. After a third-person possessive (“pronominal n”)
When a case ending follows -(s)ı (his/her/its) or -ları (their), an n is added, even before consonant-initial endings:
- evi (his house) → evine (to his house), evinde (in his house), evinden (from his house), evini (his house, object)
- arabası (her car) → arabasına, arabasında, arabasını
- Türk kahvesi → Türk kahvesini severim. — I like Turkish coffee.
Compare eve (to the house) with evine (to his house).
Ş: only for distributive numbers
Ş is the rarest. It joins the distributive suffix -er/-ar (“each”) to numbers ending in a vowel:
| Number | Distributive | Meaning |
|---|---|---|
| iki (2) | ikişer | two each |
| altı (6) | altışar | six each |
| yedi (7) | yedişer | seven each |
| bir (1) | birer | one each (no buffer) |
| dört (4) | dörder | four each (t → d) |
- Çocuklara ikişer elma verdim. — I gave the children two apples each.
See Turkish numbers for more.
Exceptions worth knowing
- su (water) and ne (what) use y where you’d expect s or n: suyu (his water / the water), suyun (of the water), neyin (of what), neyi (what, as object).
- ben and biz have irregular genitives: benim, bizim (not benin).
- Present continuous -iyor does not use a buffer; the stem’s final vowel drops instead: bekle- → bekliyor, anla- → anlıyor.
- Loanwords may contain two vowels inside the word (saat, aile, şiir, kaos). The rule applies at suffix boundaries.
A quick decision routine
When you add a suffix, run through three questions:
- Do two vowels meet? If the word ends in a consonant or the suffix starts with a consonant, you need no buffer (the pronominal n after a possessive is the one exception).
- Which suffix is it?
- genitive → n (kapının)
- third-person possessive → s (kapısı)
- distributive -er → ş (ikişer)
- everything else (cases, verb suffixes, “to be”, the question particle) → y (kapıyı, kapıya, okuyacak, hastayım)
- Which vowel? Apply vowel harmony to the suffix as usual.
Buffers in long words
One word can contain several buffers:
- oku-y-abil-ecek-ler → okuyabilecekler — they will be able to read
- araba-s-ı-n-ı → arabasını — his car (as object)
- anne-m-in kız kardeş-i-n-e → annemin kız kardeşine — to my mother’s sister
The question particle takes y too: mi + im → miyim, as in Kapıyı açabilir miyim? (Can I open the door?).
More example sentences:
- Kediyi gördün mü? Annesinin yanında. — Have you seen the cat? It’s next to its mother.
- Arabanın kapısını kapattım. — I closed the car door.
- Bu odaya kimse girmesin. — Nobody should go into this room.
Common mistakes
- No buffer at all: arabaı, kedie → arabayı, kediye.
- Y instead of s for “his”: Arabayı yeni → Arabası yeni (His car is new).
- Forgetting the pronominal n: evide, arabasıda → evinde, arabasında.
- Genitive with y: annenin, not anneyin.
- Treating su like other nouns: susu, sunun → suyu, suyun.
- Buffer after a consonant: Ahmet’yi → Ahmet’i.
Mini-exercise
Add the suffix with the right buffer letter.
- oda + accusative (the room) → ?
- oda + possessive (her room) → ?
- Fatma + genitive (Fatma’s) → ?
- bu + dative (to this) → ?
- annesi + locative (at his mother’s) → ?
- üç / beş / altı + distributive → ?
Answers: 1. odayı 2. odası 3. Fatma’nın 4. buna 5. annesinde 6. üçer, beşer, altışar
Practice this
Drop long words such as arabasından into the suffix deconstructor to spot each buffer letter, and pair this page with the vowel harmony rules that choose the vowels around them.
