/euh roh"beuh/ ; Sp. and Port. /ahrdd rddaw"bah/ , n. , pl. arrobas /-beuhz/ ; Sp. and Port. /-bahs/ .
1. a Spanish and Portuguese unit of weight of varying value, equal to 25.37 pounds avoirdupois (9.5 kilograms) in Mexico and to 32.38 pounds avoirdupois (12 kilograms) in Brazil.
2. a unit of liquid measure of varying value, used esp. in Spain and commonly equal (when used for wine) to 4.26 U.S. gallons (16.1 liters).
[ 1590-1600; al rub' the fourth part, i.e., a quarter of the qintar; see QUINTAL ]