What is Nipple On?
1.
When a male or females nipple becomes erect by cold temperatures or the touching/licking/pinching/biting/twisting of the nipple.
Dude its so cold in here I could cut glass with this nipple on.
I just got a hard on from staceys huge and very noticable nipple on.
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2.
When the weather is so cold that a girls nipples are erect through their bra and top, or a guys nipples can be seen through thick clothing.
This can be expanded to be 'Nipples on my feet' to mean a certain body part to be cold that doesn't actually have nipples.
Girl: It's a bit of a nipple on today
Guy: Yeah it's freezing isnt it
Girl: Yeah I've got nipples on my feet!
See
