bezel

noun

1. a sloping surface, as the cutting edge of a chisel
2. the slanting faces of the upper part of a cut gem, esp. a brilliant; also, this part of a gem
3. 1. the groove and flange holding a gem, watch crystal, etc. in place
   2. a rotatable rim on a watch or clock, that can be moved to indicate certain kinds of data: an elapsed-time bezel