Someone who chases metal; a person who decorates metal by engraving or embossing.
A tool used for cleaning out screw threads, either as an integral part of a tap or die to remove waste material produced by the cutting tool, or as a separate tool to repair damaged threads.
From Middle English chaser, chacer, chasour, borrowed from Old French chaceür, chaceor, from chacier; later senses from or influenced by chase + -er. chasseur.