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Related to tack up: tack onto
tack something up
to fasten something onto something with tacks. The drapes started to fall, so we tacked them up again. Please tack up these posters.
1. To post something with or as if with a tack: I tacked up a poster of my favorite band. The teacher tacked the best students' essays up on the wall.
2. To outfit a horse with a harness and saddle: The cowboy tacked up the horse. We can take the horses out for a ride after you've tacked them up.