Ru″by (?), n.; pl.Rubies (#). [F. rubis (cf. Pr. robi), LL. rubinus, robinus, fr. L. rubeus red, reddish, akin to ruber. See Rouge, red.] 1. (Min.) A precious stone of a carmine red color, sometimes verging to violet, or intermediate between carmine and hyacinth red. It is a red crystallized variety of corundum.
☞ Besides the true or Oriental ruby above defined, there are the balas ruby, or ruby spinel, a red variety of spinel, and the rock ruby, a red variety of garnet.
Of rubies, sapphires, and pearles white. Chaucer.
2. The color of a ruby; carmine red; a red tint.
The natural ruby of your cheeks. Shak.
3. That which has the color of the ruby, as red wine. Hence, a red blain or carbuncle.
4. (Print.) See Agate, n., 2.
5. (Zoöl.) Any species of South American humming birds of the genus Clytolæma. The males have a ruby-colored throat or breast.
Ruby of arsenic, Ruby of sulphur(Chem.), a glassy substance of a red color and a variable composition, but always consisting chiefly of the disulphide of arsenic; — called also ruby sulphur. — Ruby of zinc(Min.), zinc sulphide; the mineral zinc blende or sphalerite. — Ruby silver(Min.), red silver. See under Red.