A play off the popular number Too Legit to Quit by the preeminent MC Hammer, this phrase is used with pride by classy ladies (and some men) to describe their aversion to public toilets.
1) An MC Hammer song made in 1991
2) One of the many hilarious quotes from the 2007 movie HOTROD. Where Rod Kimble explains how he was once legit, almost to legit to quit.
I used to be legit. I was too legit. I was too legit to quit. but now I'm not legit. I'm unlegit. And for that reason, I mustquit.
When your riding on a coach and need to lay a spicy log, but you don't want to risk your fellow passengers taking in the potent fumes and judging you. So you hold it in till the nextservice station.
Guy1: I'm going to sack off squeezing this lemon and hold it in