RTE Guide

[fuzzy-brain]

17d: They're not even to be coupled! (3,3,3) _ D _ M _ N _ U _.
I've answered this as 'Odd Men Out' but I've seen it answered here a couple of times as 'Odd MAN Out'.
Any ideas as to why it should be one or the other?

[factor-fiction]

I agree with you

[fuzzy-brain]

Thanks for that, factor30.

[factor-fiction]

I don't understand the wordplay though- clearly 'not even' = 'odd' but I can't explain the rest

[factor-fiction]

...other than the fact that someone who isn't paired up is an 'odd man out'.
Actually, maybe the word THEY has been misused here as a singular- that would make the answer 'odd man out' after all

[fuzzy-brain]

It's a conundrum to be sure!