doktorat

1. (equivalent to a PhD) doctorate; doctoral degree; PhD
   Radi doktorat na Filozofskom fakultetu. — He's doing his PhD at the Faculty of Philosophy.
   Doktorat je stekla u Beču. — She got her doctorate in Vienna.
2. (of the written work) doctoral thesis; dissertation
   Prošle nedelje je odbranila doktorat. — She defended her doctoral thesis last week.

Serbian doktorat corresponds to a PhD, i.e. in level to the Russian кандидат наук, not доктор наук: in Serbia doktor nauka is the first and only degree after the master's. Typical collocations: raditi doktorat "to do a PhD", odbraniti doktorat "to defend a thesis".