Definite noun compounds (-nin ... -si)

Definite Noun Compounds

In Turkish, to link two specific nouns together—like "the computer's screen" or "the door of the house"—you create a definite noun compound (belirtili isim tamlaması).

Just like expressing ownership with people, you attach the genitive suffix to the first noun (the "owner") and the 3rd-person possessive suffix to the second noun (the "owned" item). Both suffixes follow 4-way vowel harmony.

First Noun + -(n)ın / -(n)in / -(n)un / -(n)ün Second Noun + -(s)ı / -(s)i / -(s)u / -(s)ü

Buffer Consonants

Remember that Turkish avoids placing two vowels next to each other.

• If the first noun ends in a vowel, insert the buffer n before the genitive suffix (-nın, -nin, etc.).
• If the second noun ends in a vowel, insert the buffer s before the possessive suffix (-sı, -si, etc.).

Consonant Mutation

When adding these vowel-starting suffixes to nouns ending in hard consonants (like p, ç, t, k), the final consonant often softens.

• p softens to b (e.g., kitap becomes kitabın)
• k softens to ğ (e.g., uçak becomes uçağın)
• t softens to d (e.g., kilit becomes kilidi)

Plurals in Compounds

If the second noun is plural, simply attach the plural suffix (-lar or -ler) before the possessive suffix. Because the plural suffix ends in a consonant, you will attach the possessive suffix directly without a buffer s (just -ı or -i).