A little face; a small, plane surface; as, the facets of a diamond.
- One of the flat polished surfaces cut on a gemstone or occurring naturally on a crystal.
- Anatomy A small, smooth, flat surface, as on a bone or tooth.
- Biology One of the lenslike visual units of a compound eye, as of an insect.
- One of numerous aspects, as of a subject. See Synonyms at phase.