The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D. Copyright (C) 2007 by HarperCollins Publishers. Cite This Source
Idioms and Phrases with shoot oneself in the foot
shoot oneself in the foot
Foolishly harm one's own cause, as in He really shot himself in the foot, telling the interviewer all about the others who were applying for the job he wanted. This colloquial term alludes to an accidental shooting as opposed to a deliberate one done so as to avoid military service.