(Homonym: bitt).
1. A small fragment of something broken off from the whole; SYN. chip, flake, fleck, scrap.
2. Piece of metal held in horse's mouth by reins and used to control the horse while riding.
3. The cutting part of a drill; usually pointed and threaded and is replaceable in a brace or bitstock or drill press.

(Slang) teeth; dice; keys of a piano

Plural of tooth