The semi-erect state of a mans penis in response to initial feelings of arousal. It describes the hanging, yet hard penis as opposed to erect, upward state of an aroused penis.
Woman: My fella, I feel a nice hang-hard action going on there in your pants! Got me wet with my nips all hard now!!
Man: Yeah babe you got me hyped up with that sexy little fit you're wearing and you keep grindin my little man so he's hangin-hard for you boo!!
A well endowed guy that has a penis tip that extends past the balls in the semi-aroused to fully aroused state, hence hanging hard.
Gary: Whoa girl, your booty is looking mighty nice tonight!! You better stop tempting me cuz its getting too obvious my meat on hang-hard status!!
Azeria: Thats a nice big hang-hard you got there G!! Got me nice and moist!!