Wiktionary
drop trou
vb. 1 (context US intransitive English) To drop one's trousers and/or undershorts; to moon 2 (context by extension English) to strip, undress, get naked
Usage examples of "drop trou".
Otherwise, why would she keep writing all those scenes in which Pete Logan was required to drop trou?
In fact, the only men who tried to date such women were the arrogant assholes who thought every woman wanted them to drop trou and let the poor bitch have a glimpse of Dr.
I don't care if you have to drop trou and dance the hootchie-koo, just get them to land!