beater-upper

plural beater-uppers

1. One who beats people up.

   These are the muggers and beater-uppers, and car thieves and burglars and rapists, assaulters, and so on.

   1965, Hearings [Agriculture dept.]

   2 more examples

   Yesterday he was doing just that by submitting to a thorough beating up at the hands of Miss Lupe Velez, who's probably the best beater-upper of either sex in Hollywood.

   1941 August 11, “Barrymore Beaten Up While Working For His Creditors”, in St. Petersburg Times

   […] and, in the best sporting tradition, the Gordon player gratefully helped his beater-upper back to his feet.

   1985 May 27, “A pug and a gentleman”, in The Sydney Morning Herald