This is the 12579th most frequent Turkish word.
ikiz
Twin.
The word 'ikiz' is used to describe a sibling who was born at the same time as the person. It functions as a noun.
O benim ikiz kardeşimdir.
He is my twin brother.
Here, 'ikiz' is pluralized as 'ikizler' to refer to twin siblings in a general context. It is a noun.
Bu film ikizler hakkında.
This movie is about twins.
The word 'ikiz' is used metaphorically to describe a pair of stars that are linked in orbit. It acts as an adjective.