low blow

American  

noun

1. (in boxing) an illegal blow below the waist of an opponent.

2. an unfair or unsportsmanlike criticism or attack.

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low blow Idioms  

1. 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]

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Etymology

Origin of low blow

First recorded in 1950–55

Example Sentences

That’s a lie, Soboroff shot back, claiming he was insulted by the low blow.

From Los Angeles Times • Dec. 15, 2025

It sounds like a low blow, and an odd attack line in a diverse state filled with immigrants and newcomers of all kinds.

From The Wall Street Journal • Oct. 10, 2025

There was controversy the last time they fought when Usyk was floored in the fifth round but the punch was declared a low blow by the referee.

From BBC • Apr. 28, 2025

Former President Trump, on the other hand, appeared to chuckle at the low blow.

From Salon • Oct. 18, 2024

It was a punch in the gut, a low blow.

From "The Girl on the Train" by Paula Hawkins