Etymology · Proto-Indo-European
*bʰus-
1 English words descend from Proto-Indo-European *bʰus-, most common first.
- boltA (usually) metal fastener consisting of a cylindrical body that is threaded, with a larger head on one end. It can be inserted into an unthreaded hole up to the head, with a nut then threaded on the other end; a heavy machine screw.