Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
captain [ˈkæptɪn] n (of ship, plane) команди́р; (of team, army) капита́н
vt (ship) кома́ндовать (impf) +instr ; (team) явля́ться (impf) капита́ном +gen
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.