Толковый словарь английского языка Oxford English Reference - flyweight

n. 1 a weight in certain sports intermediate between light flyweight and bantamweight, in the amateur boxing scale 48-51 kg but differing for professionals, wrestlers, and weightlifters. 2 a sportsman of this weight. Phrases and idioms light flyweight 1 a weight in amateur boxing up to 48 kg. 2 an amateur boxer of this weight.