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low blow

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noun
  1. (in boxing) an illegal blow below the waist of an opponent.
  2. an unfair or unsportsmanlike criticism or attack.

Origin of low blow

First recorded in 1950–55
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for low blow

insult
Idioms and Phrases with low blow

low blow

An unscrupulous attack; an insult. For example, When my roommate moved out without a word of warning, leaving me to pay the entire rent, that was a low blow, or She wanted to win the argument, but bringing up his failed marriage was a low blow. This term alludes to the illegal practice of hitting an opponent in boxing below the belt. [c. 1950]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.