pseto

1. derog. cur; mutt
   Neko pseto je celu noć lajalo ispod prozora. — Some mutt was barking under the window all night.
2. derog. (of a person) cur; scoundrel
   To pseto me je prevarilo i pobeglo s parama. — That scoundrel cheated me and ran off with the money.

The word is insulting; the neutral word for a dog is "pas".