The definition of a thief is a person who takes something without permission or without the owner knowing.noun
An example of a thief is someone who steals wallets out of back pockets.YourDictionary definition and usage example. Copyright © 2013 by LoveToKnow Corp.
noun pl. thieves
Origin: ME < OE theof, thiof, akin to Ger dieb < IE base *teup-, to cower, lurk
Used by arrangement with John Wiley & Sons, Inc.
noun pl. thieves thieves
Origin: Middle English, from Old English thēof.