neodređeno

1. vaguely
   Odgovorio je neodređeno i promenio temu. — He gave a vague answer and changed the subject.
   Samo je neodređeno slegnula ramenima. — She just shrugged vaguely.
2. colloq. (na neodređeno, of a job) indefinitely; on a permanent contract
   Konačno sam dobio posao na neodređeno. — I finally got a permanent job.
   Da li si zaposlena na određeno ili na neodređeno? — Are you on a fixed-term or a permanent contract?

The phrase na neodređeno (vreme) is very often used of employment contracts.