This is the 8755th most frequent Turkish word.
saçınız
"Your hair" (formal or plural).
In this sentence, 'saçınız' refers to hair and includes the possessive pronoun 'your' indicating who the hair belongs to.
Saçınız çok güzel görünmüş bugün.
Your hair looks very beautiful today.
Here, 'saçınız' again means hair, with the possessive form showing it's referring to the listener's hair, and the verb provides context about a service performed.
Kuaförünüz saçınızı çok iyi kesmiş.
Your hairdresser has cut your hair very well.
In this sentence, 'saçınız' is used in the context of mentioning hair in relation to a product, describing its usefulness.