WordNet (r) 3.0 (2006):

bantamweight
    n 1: weighs 115-126 pounds
    2: an amateur boxer who weighs no more than 119 pounds

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "bantamweight":
   Chinese boxer, black belt, boxer, brown belt, bruiser, catchweight,
   featherweight, fighter, fisticuffer, flyweight, heavyweight,
   karate expert, light heavyweight, lightweight, middleweight,
   palooka, prizefighter, pug, pugilist, savate expert, sparrer,
   underweight, welterweight