a horse of another colour

horse of another color

Something completely different or separate, especially in comparison to something else. I've always found math to be easy, but calculus is a horse of a another color.
See also: another, color, horse, of
Farlex Dictionary of Idioms.

a horse of another (or different) colour

a thing significantly different.
1975 Sam Selvon Moses Ascending Two or three is okay, but when you start bringing in a battalion, it is a horse of a different colour.
See also: another, colour, horse, of
Farlex Partner Idioms Dictionary
See also:
  • a horse of another
  • a horse of another color
  • (you) wanna make something of it?
  • a fast talker
  • (you've) got to get up pretty early in the morning to (do something)
  • a/the feel of (something)
  • (I) wouldn't (do something) if I were you
  • all righty
  • a straw will show which way the wind blows
  • a crack at (someone or something)