featherweight

noun

1. A weight class in many combat sports; e.g. in professional boxing of a maximum of 126 pounds or 57.2 kilograms.

   “Safety and fairness in female sport was one of the most prominent topics at this summer’s Olympic Games, where boxers Imane Khelif and Lin Yu Ting took gold in the women’s welterweight and featherweight categories respectively.”

2. A sportsman who fights in this division.

   “Watson specializes in adiposeness; none of his chorus beauties may be considered featherweights.”

3. The lightest weight that may be carried by a racehorse.