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

It was almost a turning of the tide, only for Pimblett's momentum to be halted by a low blow call.

From BBC

Was this how England fans are still seen internationally or just a low blow?

From BBC

"It feels amazing. I whooped that boy in his back yard," Londoner TKV, who was deducted a point for a low blow, said.

From BBC

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

Considering how the streaming era has already made a big dent in many artists' incomes, Emily Portman says this affair has felt like a "very low blow".

From BBC