From Longman Dictionary of Contemporary Englishbantamweightban‧tam‧weight /ˈbæntəmweɪt/ noun [countable] DSOa boxer who weighs less than 53.52 kilograms, and who is heavier than a flyweight but lighter than a featherweight
Examples from the Corpus
bantamweight• Wayne McCullough, the best bantamweight around.• Boxing: Gold medals are awarded in light flyweight, bantamweight, lightweight, welterweight, middleweight and heavyweight. 