1. A unit of weight formerly used in Spanish-speaking countries, equal to about 11.3 kilograms (25 pounds).
2. A unit of weight formerly used in Portuguese-speaking countries, equal to about 14.4 kilograms (32 pounds).
3. A liquid measure formerly used in Spanish-speaking countries, having varying value but equal to about 16.2 liters (17 quarts) when used to measure wine.
[Spanish and Portuguese, both from Arabic ar-rub', the quarter (of a quintal) : al-, the + rub', quarter; see rbʿ in the Appendix of Semitic roots.]
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