Word Study
charley horse
OXFORD DICTIONARY
charley horse, n. US sl. stiffness or cramp in an arm or leg.
Etymology
19th c.: orig. uncert.
THESAURUS
charley horse
acute pain, bite, boring pain, cramp, cramps, crick, darting pain, fulgurant pain, girdle pain, gnawing, griping, hitch, jumping pain, kink, lancinating pain, nip, pang, paroxysm, pinch, prick, seizure, sharp pain, shoot, shooting, shooting pain, spasm, stab, stabbing pain, stitch, thrill, throes, tormen, tweak, twinge, twitch, wrenchFor further exploring for "charley horse" in Webster Dictionary Online