odd one out

(the) odd one out

1. Someone who is excluded from or left out of a group for some reason. Ever since my injury, I've been odd one out when my friends go to play football together. John never really fit in with others. Even in elementary school, he was usually the odd one out.
2. Something or someone that is decidedly or markedly different, atypical, or unusual in comparison to others in a group. My clunky old truck is quite the odd one out next to all my coworkers' flashy new sports cars. You're going to be the odd one out if you go to a dinner party dressed like that!
See also: odd, one, out
Farlex Dictionary of Idioms.

odd one (or man) out

1 someone or something that is different to the others. 2 someone who is not able to fit easily or comfortably into a group or society.
See also: odd, one, out
Farlex Partner Idioms Dictionary

the odd man/one ˈout

a person or thing that is different from others or does not fit easily into a group or set: That’s the problem with 13 people in a group. If you need to work in pairs, there’s always an odd one out. Tom is nearly always the odd man out. He never wants to do what we want to do, or go where we want to go.
See also: man, odd, one, out
Farlex Partner Idioms Dictionary
See also:
  • (the) odd one out
  • (the) odd man out
  • odd man out
  • the odd man/one out
  • bring (someone) in from the cold
  • odd and curious
  • on the outside looking in
  • on the outside, looking in
  • fruit
  • fruiter