- 1 [transitive] tack something + adv./prep. to fasten something in place with a tack or tacks synonym nail He tacked a notice on the bulletin board.
- 2 [intransitive] (technology) to change the direction of a sailing boat so that the wind blows onto the sails from the opposite side; to do this several times in order to travel in the direction that the wind is coming from
- 3 [transitive] tack something (+ adv./prep.) to fasten pieces of cloth together temporarily with long loose stitches before sewing them finally She tacked the sleeve of the blouse into the armhole. Phrasal Verbstack somethingon
NAmE//tæk//Verb Forms present simple I / you / we / they tack
he / she / it tacks
past simple tacked
-ing form tacking