There is a Greek word here and there is a Turkish word in Greek, masa that means eating, plural mases, eating many times, an informal word used in the popular songs with buzuki, the so called rebetiko. All these words are oriental, Arabic, Farsi, Turkish. And many words from Greek, as liman, kaptan (Byzantine title "katepano", passed to Italian, capitano and came back to Greek as kapetanios and kaptan in Turkish, etc.
It’s because the possessive “-ın” to cant be put directly after a vowel, so an extra n is added between the object and the suffix (masaNın). It could also mean on your table though (: Maybe this is helpful https://www.turkishexplained.com/possessiverelationship.htm