Libra (n.) Look up Libra at Dictionary.com
zodiac constellation, late Old English, from Latin libra "a balance, pair of scales," also "pound (unit of weight)," from Proto-Italic *leithra- "pound." Nativized in Old Norse as skala-merki. De Vaan compares Greek litra "name of a Sicilian coin," which "was probably borrowed from an Italic language at the stage containing [-thr-]