side' arm" Mil.
a weapon, as a pistol or sword, carried at the side or in the belt.
side•armPronunciation: (sīd'ärm"), [key]
with a swinging motion of the arm moving to the side of the body at shoulder level or below and nearly parallel to the ground: to pitch sidearm.
thrown or performed sidearm: a sidearm curve ball; sidearm stroke.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.