rogonja

1. colloq. derog. (of a husband) cuckold
   Svi su znali da je rogonja, osim njega. — Everyone knew he was a cuckold except him.
   Ne želim da ispadnem rogonja pred celim krajem. — I don't want to look like a cuckold in front of the whole neighbourhood.
2. (of an animal) horned animal, especially a large-horned ox
   Seljak je vodio starog rogonju na pašu. — The peasant was leading the old big-horned ox out to pasture.

In the sense 'cuckold' the word is insulting and is mostly used as mockery or an insult.