fly in the face of something

fly in the face of something

COMMON If something flies in the face of accepted ideas, rules, or practices, it goes against them. The plan to sell rhino horn flies in the face of the international ban. The Institute flew in the face of accepted opinion and published research suggesting the world may not be getting hotter. Note: The reference here is to a dog attacking someone by leaping or flying at their face.
See also: face, fly, of, something