This is the 14042nd most frequent Turkish word.
mezarının
"Mezarının" means "of his/her/its grave" in English.
Mezarının is used in the genitive form to indicate possession of the grave, meaning 'her/his grave'.
Mezarının başında dua ettim.
I prayed at her/his grave.
Mezarının is used to specify 'his/her grave,' indicating possession in the sentence.
Bu kitabı mezarının üstüne koymuşlar.
They placed this book on her/his grave.
Mezarının denotes possession and is combined with 'yerini' to form 'the location of her/his grave.'