[@Saltwater Thief] Serbian .... or serbo-croatian, or bosnian or the newest one montenegrin... The languages in this part of world are weird. 

 Anyway Serbian is the shortest answer to your question ^^
And if you want to know exactly its used for small bunnies. 
Bunny - Zec
Bunnies - Zecevi
Small bunny - Zeka
Small bunnies - Zeke