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.
See thief in Webster's New World College Dictionary
noun pl. thieves
Origin: ME < OE theof, thiof, akin to Ger dieb < IE base *teup-, to cower, lurk
See thief in American Heritage Dictionary 4
noun pl. thieves thieves (thēvz)
Origin: Middle English
Origin: , from Old English thēof.
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