This is the 6819th most frequent Turkish word.
birinin
"Birinin" means "someone's" or "of someone" in English.
In this sentence, 'birinin' is used in a genitive form indicating possession, meaning 'someone's'.
Birinin yardımına ihtiyacım var.
I need someone's help.
Here, 'birinin' also functions in a possessive/genitive sense to convey ownership or relation ('someone's opinion').
Birinin fikrini duymak istiyorum.
I want to hear someone's opinion.
In this case, 'birinin' signifies 'someone's' in relation to feelings, underscoring the possessive connection.