Resistance of a material to local plastic deformation
Diamond has a greater hardness than any other natural material.
by Douglas Cheaterson October 10, 2007
cool, really outstanding, look nice.
Them shoes go hard. Your hair go hard.
by Cam April 8, 2003
"Last party we went to had a bunch of bitch-beers and no hard A."
by shackledxdollie November 21, 2004
Long Dong Silver could never get a real hard on, because his penis was so long.
by Jorge December 6, 2002
When the penis is aroused and expands to it's full length
Kiersten : Mmmmmmmm! Mmmmmmmm!
Chad : Mmmmmmmmm! Mmmmmmmm!
Kiersten : I do love kissing you Chad and it makes you get A Hard On would you like a blowjob?
Chad : Yes Please!
Chad : Ahhhhhhhhhhhhhhhhhh! Ahhhhhhhhhhhhhhhhh! Ahhhhhhhhhhhhhhhh!
Chad : You know this reminds me of the other day when me and Jim were kissing we got Hard On's and took turns sucking each other's dicks!
Kiersten : Reallly I just gave you an amazing blowjob and your going to talk about your gay experience with Jim.
Chad : I'm not gay I'm bicurious!
Kiersten : Well sounds like your gay to me!
Chad : I gotta go Jim want's me to take A shower with him!
Kiersten : GAY!
Chad: Bicurious!
by SlopNChop March 7, 2017