1
general::
Phrase(s): odd man out
an unusual or atypical person or thing. • I’m odd man out because I’m not wearing a tie. • You had better learn to use the new system software unless you want to be odd man out.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
1. A person who is left out of a group for some reason, as in The invitation was for couples only, so Jane was odd man out. [Mid-1800s] 2. Something or someone who differs markedly from the others in a group, as in Among all those ranch-style houses, their Victorian was odd man out. [Late 1800s]
American Heritage Idioms