Definition of buff

Word Originnoun senses 2 to 3 mid 16th cent.: probably from French buffle, from Italian bufalo, from late Latin bufalus, from earlier bubalus, from Greek boubalos ‘antelope, wild ox’. The original sense in English was ‘buffalo’, later ‘oxhide’ or ‘colour of oxhide’. noun sense 1 early 20th cent.: from the colour buff, originally applied to enthusiastic fire-watchers, because of the buff uniforms formerly worn by New York volunteer firemen.