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3.
Nipple hard on.
Sarah: "do i have N.H.Os?"
Amanda: "yes"
by Tomanda February 18, 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
 
2.
NHO
Nipple Hard On
You can tell she has NHO bad
by Swimmer May 20, 2003