tack(redirected from tack on)
Also found in: Dictionary, Thesaurus, Medical, Legal, Financial, Idioms.
(Russian, gals; from Dutch hals). (1) The course of a vessel with respect to the wind (for example, a vessel is moving on a starboard tack when the wind is blowing toward the starboard side of a vessel).
(2) The segment of a vessel’s course from turn to turn while maneuvering under sail, carrying out measuring operations, sweeping mines, fishing, and so on.
(3) A rope securing the lower windward corner of the sail (the tack corner) to a mast.