bad-mouth

or bad·mouth

[ bad-mouth or, sometimes, -mouth ]
/ ˈbædˌmaʊθ or, sometimes, -ˌmaʊð /

verb (used with object), bad-mouthed, bad-mouth·ing.

Slang. to speak critically and often disloyally of; disparage: Why do you bad-mouth your family so much?

Origin of bad-mouth

1935–40; originally a curse, spell (the sense recorded in Gullah); compare Vai (Mande language of Liberia and Sierra Leone) dà nyà mà curse, literally, bad mouth

OTHER WORDS FROM bad-mouth

bad-mouth·er, noun

British Dictionary definitions for bad mouth

bad-mouth

verb

(tr) slang to speak unfavourably about

Idioms and Phrases with bad mouth

bad mouth

Disparage or criticize unduly, malign, as in Why do you constantly bad mouth your colleagues? This term is believed to be of African origin, where the phrase bad mouth signifies a curse or evil spell. [1930s]