Anything that pulls, but especially a hoist in which a cable is attached to a lever and a ratchet mechanism(noun)
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Use "puller" in a sentence
"Sometimes it takes a few good whack if the bullet has a good cannelure, but a design feature of a bullet puller is the assumption you want to save the brass."
"A classic liberal switch-puller is “He’s a Republican.”"
"I was at a sporting clays shoot and some body shot the "puller" or "trapper"."