-luby-

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. [ 1913 Webster ]

☞ 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. [ 1913 Webster ]

Of rubies, sapphires, and pearles white. Chaucer. [ 1913 Webster ]

2. The color of a ruby; carmine red; a red tint. [ 1913 Webster ]

The natural ruby of your cheeks. Shak. [ 1913 Webster ]

3. That which has the color of the ruby, as red wine. Hence, a red blain or carbuncle. [ 1913 Webster ]

4. (Print.) See Agate, n., 2. [ Eng. ] [ 1913 Webster ]

5. (Zool.) Any species of South American humming birds of the genus Clytolaema. The males have a ruby-colored throat or breast. [ 1913 Webster ]

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. [ 1913 Webster ]