1 definition by hot noodles
Nipple Protrusion; when you can see an individual's erect nipples through their clothing, intentional or unintentional. Can be a result of sexual excitement/arousal or (un) favorable temperature.
Person 1: Dude, did you see that gal just walk by with all that NP?
Person 2: Yeah man, she needs to get a thicker bra or something!
laughter
Person 2: Yeah man, she needs to get a thicker bra or something!
laughter
by hot noodles May 31, 2013