[noun] (nautical) a line (rope or chain) that regulates the angle at which a sail is set in relation to the wind Synonyms: sheet, mainsheet, weather sheet, shroud
[noun] (nautical) the act of changing tack Synonyms: ing
[noun] sailing a zigzag course
[verb] fasten with tacks; "tack the notice on the board"
[verb] turn into the wind; "The sailors decided to tack the boat"; "The boat tacked" Synonyms: wear round