Green’s Dictionary of Slang

mo v.2

[mo n.1 (4)]

(US/UK teen) to act towards someone in a manner that is perceived as being homosexual.

[US]L. Birnbach Official Preppie Hbk 222: Stop moing me...Don’t touch me. When boys inadvertently touch each other in elementary and secondary school; homophobic. (Also, mo, moing out, heavy mo action).