Odd Man Out

  1. A person who is left out of a group for some reason. 2. Something or someone that differs markedly from the others in a group.

Examples:

  • The invitation was for couples only, so Jane was odd man out.
  • Among all those ranch-style houses, their Victorian was odd man out.

Origin: Mid-1800s (sense 1); Late 1800s (sense 2)