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2.
NHO
Nipple Hard On
You can tell she has NHO bad
by Swimmer May 20, 2003
 
1.
NHO
Nipple Hard On
NHO's are usually caused by being cold or aroused. They can be sexy when seen on a female, even if displayed through several layers of clothing.
My NHO's are so bad I could cut glass!
by magicalheather October 12, 2004
 
3.
Nipple hard on.
Sarah: "do i have N.H.Os?"
Amanda: "yes"
by Tomanda February 18, 2003