A chaika (Russian: чайка,Ukrainian: чайка, chayka, Hungarian: csajka, Polish: czajka, Serbian: шајка / šajka, Slovene: šajka or plitka) was a wooden boat that could have a mast and sail, a type of galley, used in early modern warfare and cargo transport by the: Tschaika were either 48 m (157 ft) (Double Tschaika), 24 m (79 ft) (Ganz ("Full") Tschaika), 12 m (39 ft) (Halb ("Half") Tschaika) or 6 m (20 ft) (Quarter Tschaika) in length, operated by sail or oars.

Between 30 and 50 men were in service, commanded by an officer, with a helmsman, an armourer, a drummer, two bowsmen, and up to 36 oarsmen.

The bottom of a chaika was carved out of a single tree trunk, with sides built out of wooden planks.

Some chaikas also had two steering oars, so that the boat never needed turning around in order to switch direction.

[citation needed] A similar, but larger boat used by the Zaporozhian Cossacks for both transport and warfare was called a baidak.