What does "below the belt" mean?

disregarding the rules (from the notion of an illegal low blow in boxing)

What is a synonym for "below the belt"?

Common synonyms include: foul, not cricket, unfairly.

Pronounced //bəˈloʊ ðə bɛlt//.

/bəˈloʊ ðə bɛlt/ prep_phrase

prep_phrase ·Rare ·Advanced level

Adjective

1
disregarding the rules (from the notion of an illegal low blow in boxing) wordnet

Adverb

Prep_phrase

1
Of a punch, landing illegally, below the opponent's waist.
2
Unfair; dirty; not according to the generally accepted rules. broadly, idiomatic
"Commenting on his bachelorhood in a debate on marital ethics was a bit below the belt, don't you think?"

"Commenting on his bachelorhood in a debate on marital ethics was a bit below the belt, don't you think?"