Where does “ћилибар” come from?

ћилибар (Serbo-Croatian) comes from Ottoman Turkish كهلبار, from Persian کهربا, from Persian کاه, from Persian کاستن, from Proto-Iranian kas-, from Proto-Indo-European kʷeḱ- — to see; to look.

ћилибар (Serbo-Croatian): amber

Definitions

amber

Ancestry of “ћилибар”, step by step

Step	Language	Word	Meaning
1	Ottoman Turkish	كهلبار	vulgar form of كهربا
2	Persian	کهربا	amber
3	Persian	کاه	chaff; straw; hay
4	Persian	کاستن	to decrease
5	Proto-Iranian	kas-	to be small, diminish, lessen
6	Proto-Indo-European	kʷeḱ-	to see; to look

Every word from Proto-Indo-European kʷeḱ- →Every word from Proto-Iranian kas- →Every word from Persian کاستن →