Ruby (?), 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.
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&hand_; 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.
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Of rubies, sapphires, and pearles white. Chaucer.
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2. The color of a ruby; carmine red; a red tint.
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The natural ruby of your cheeks. Shak.
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3. That which has the color of the ruby, as red wine. Hence, a red blain or carbuncle.
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4. (Print.) See Agate, n., 2. [Eng.]
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5. (Zoöl.) Any species of South American humming birds of the genus Clytolæma. The males have a ruby-colored throat or breast.
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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.
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Ruby, v. t. [imp. & p. p. Rubied (?); p. pr. & vb. n. Rubying.] To make red; to redden. [R.] Pope.
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