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libra f. (Noun) "pound"
13th cent. From Latin libra "pound," "balance." The meaning of a pound is probably the original sense of the word. From Proto-Italic *leiþra- "pound," and perhaps "coin." Of unknown origin. Probably borrowed from another language.
Indo-European
Romance
Portuguese libra, Galician libra, French livre, Italian libra, livră
Hellenic
Ancient Greek λίτρα (lítra) "Sicilian coin equivalent to 50 drachmes," "pound." As the Proto-Hellenic form was *līþrā, it looks like the word was borrowed from Proto-Italic *leiþra-, however, one could just as easily assume both *līþrā and *leiþra- were borrowed from a source language spoken in Sicily.