have a glass jaw

have a glass jaw

slang (of a boxer) To be apt to be knocked unconscious by one's opponent. Don't worry about that guy, he has a glass jaw—you'll have no trouble knocking him out.
See also: glass, have, jaw
Farlex Dictionary of Idioms.

have a glass jaw

Fig. to be susceptible to a knockout when struck on the head. (Said only of boxers who are frequently knocked down by a blow to the head.) When the prizefighter was knocked out cold by a right to the chin in the first round, the newspapers said he had a glass jaw. Once a fighter has a glass jaw, he's finished as a boxer.
See also: glass, have, jaw
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • hander
  • handers
  • flesh-presser
  • heller
  • bottle baby
  • hellraiser
  • hell raiser
  • by night
  • by day
  • fall through
References in periodicals archive
"He was asked if I have a glass jaw and he said 'what are you talking about, I spar with him and he's knocked lots of sparring partners out who are heavier'."