When a nipple slips in to view.
She walked out on stage with her tit falling out, it was a hell of a nip slip!
To have the nipple showing on accident. Most common in public or on live t.v.
Don had such a nip slip the other day, he got embarrassed because he was on live t.v.
The act of having your nipples exposed due to loose fitting clothes. Often embarrassing if Female
Brittany can never watch videos of her own engagement party because she had a total Nip Slip in front of her friends and family and nobody said a word
When a braless female's nipple accidentaly slips out from under a loose-fitting garment
Hold up, pause it there. Yup, total nip slip!
When a female celebrity "accidently" lets her nipple show or has her whole boob slip out. Check pictures of Lindsey Lohan.
When a nipple (more often than not, the nipple of a woman) slips out of an article of clothing, partially or fully, and is noticed by someone else.
She destroyed the nip slip photograph almost immediately
Seriously. Has nobody ever told these brainless celebrity twats that there exists a garment called BRASSIERE? What kinds of exhibitionist morons go around wearing clothes which might reveal a private body part at any given moment, anyway?
Tara Reid: your nipple is ugly.