jadac

1. (bird's bone) wishbone
   Posle ručka smo sestra i ja lomile jadac. — After lunch my sister and I broke the wishbone.
   Veći deo jaca ostao je u mojoj ruci. — The bigger piece of the wishbone stayed in my hand.
2. (traditional game) game in which two people break the wishbone and afterwards the one who accepts something from the other without saying “znam za jadac” loses
   Igrali smo jadac celo leto i niko nije uspeo da me uhvati. — We played jadac all summer and nobody managed to catch me out.
   Uzeo je čašu bez reči i tako izgubio jadac. — He took the glass without a word and so lost the jadac game.

Usually in the phrase lomiti jadac, to break the wishbone. In the game, after the bone is broken, a player who accepts anything from the other must say “znam za jadac” or else loses; hence the expression Znam ja za taj jadac, “you can't fool me with that”.