birbirlerinin

"Birbirlerinin" is a Turkish possessive pronoun. It translates to "each other's" or "of each other." It is a plural possessive form used to indicate something that belongs to or is done by two or more individuals in relation to one another.

The word is formed by combining the reflexive pronoun "birbir" (each other) with the genitive suffix "-ler" (plural possessive) and then the possessive suffix corresponding to the third person singular or plural, depending on the context of the sentence. For example, "birbirlerinin kitapları" would mean "each other's books."

"Birbirlerinin" is crucial for expressing reciprocal actions or possessions in Turkish. It avoids the need to repeat the subjects of the sentence when referring to their mutual relationships or belongings. For instance, instead of saying "Ali and Veli help Ali and Veli," one would say "Ali ve Veli birbirlerinin yardım eder," meaning "Ali and Veli help each other."

The usage of "birbirlerinin" highlights the interconnectedness or mutual engagement between the parties involved. It is a common and essential element in constructing sentences that describe shared experiences, collaborations, or reciprocal feelings.