bad mouth

bad-mouth

1. verb To speak negatively or unflatteringly about someone or something. Why are you always bad-mouthing Tiffany? You don't even know her that well!
2. noun One who says negative or unflattering things about someone or something. He's a real bad-mouth, so don't listen to anything he says about me!
Farlex Dictionary of Idioms.

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]
See also: bad, mouth
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • bad-mouth
  • dirty-mouth
  • poor-mouth
  • dog
  • dogg
  • dogs
  • cast aspersions
  • cast aspersions on
  • cast aspersions on (someone or something)
  • aspersion
References in periodicals archive
When asked the cause, the 5-year-old girl told her mother that the cleaner had kissed her on her mouth two times before and has bad mouth smell.
Cleaner jailed for kissing girl while playing
I'd never heard him bad mouth anyone and yet the abuse he got from our so called fans was disgusting.
Players mostly to blame; SUNDAY SHOUT
PAULA RADCLIFFE insists she did not bad mouth her friend Mo Farah and claims she has been misquoted.
PAULA: NO MO RIFT
How the article is worded seems mean spirited and a bit hateful to jump the gun or in this case to jump the string to tell readers to bad mouth a bow manufacturers string without first giving them an opportunity to make it right or addressing it in a more direct manner.
Winke bad?
Indeed nothing induces low spirits more than to hear fellow supporters bad mouth players they had previously accorded demi-god status in happier circumstances.
Letter: Show of support
No matter how tempting, never bad mouth anybody in front of a client.
Detroiter tip: keep foot out of mouth
Consensus, here, means that even though all participants in the decision-making process are not in total agreement or sympathy with the decisions made, they will not sabotage, bad mouth, diminish, or contradict the decision outside the group (Harris & Sherblom, 2002).
An alternative model for decision-making
He used to bad mouth her while watching the show!" Radar Online's source exclaims.
French Montana Used to Dislike Khloe Kardashian Before They Started Dating - Reports
There would be times he would bad mouth the other nation's folk but he would always say that, in times of bad, you could rely on the others of those nations to watch your back.
Family of nations; Letters.
"I'm working on not swearing around Bronx...I know I have a bit of a bad mouth," Contactmusic quoted Pete, as saying.
Pete Wentz's New Year resolution - no swearing around son
A BEFORE you bad mouth the girl's chum, I hope you've taken a long, hard look at yourself in the mirror.
I AM crazy about a girl
But I don't feel I need to bad mouth them or make a fuss." Coldplay and the Rolling Stones are said to be considering their position at EMI.
.. AND SO IS KT
But fellow pro Gary Evans is insisting Monty should be punished further and continues to bad mouth him around the circuit.
Bob Shields: Monty should take a swing at critics
But the advice to you is no different to that which I would give an under age girl - don't, even if they are going to bad mouth you, give in.
Joan's Juniors: Girls pressure boys for sex too
Canon Barry Dodds of St Michael's Church of Ireland church said: "Bobby was the sort of man who would not let one person bad mouth another or let anyone bad mouth another's organisation.
TEARS FOR DAD