(as) different as chalk and cheese

(as) different as chalk and cheese

Very different from one another or in conflict. Primarily heard in UK. Good luck getting those two to talk to each other—they're as different as chalk and cheese. My daughters are different as chalk and cheese these days—one loves baseball and the other loves ballet.
See also: and, chalk, cheese, different
Farlex Dictionary of Idioms.

as different as chalk and cheese (or like chalk and cheese)

fundamentally different or incompatible. British
The opposition of chalk and cheese hinges on their being totally different in all qualities other than their rather similar appearance.
See also: and, chalk, cheese, different
Farlex Partner Idioms Dictionary
See also:
  • as different as chalk and cheese
  • chalk
  • left, right and centre
  • left, right, and center
  • left, right, and centre
  • knock the habit
  • knock the/(one's) habit
  • a totally different ballgame
  • keep balls in the air
  • spinning