Easton's Bible Dictionary
(Hebrews peninim), only in plural (Lamentations 4:7). The ruby was one of the stones in the high priest's breastplate (Exodus 28:17). A comparison is made between the value of wisdom and rubies (Job 28:18; Proverbs 3:15; 8:11). The price of a virtuous woman is said to be "far above rubies" (Proverbs 31:10). The exact meaning of the Hebrew word is uncertain. Some render it "red coral;" others, "pearl" or "mother-of-pearl."
Noah Webster's New International Dictionary of the English Language
1. (n.) 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.
2. (n.) The color of a ruby; carmine red; a red tint.
3. (n.) That which has the color of the ruby, as red wine. Hence, a red blain or carbuncle.
4. (n.) See Agate, n., 2.
5. (n.) Any species of South American humming birds of the genus Clytolaema. The males have a ruby-colored throat or breast.
6. (a.) Ruby-colored; red; as, ruby lips.
7. (v. t.) To make red; to redden.