noun. A HUGE vagina, as viewed from the outside of the body, or determined by the amount of empty space on the inside of the body.
Tom Arnold's quote about having sex with Roseanne Barr says it all "...it's like landing a 747 in the Grand Canyon." She would be considered the owner of a "Vagiant".
OR...
I was with this chick last night, and her "vagiant" scared the living hell out of me!
An individual who is so hopelessly obsessed with being negative and weak that they engulf all of their immediate company in the dirty, moist folds of their misery.
Steve is such a Sandy Vagiant! He left his cellphone at the last bar and he won't shut the fuck about it. Hes making the entire bachelor party put our plans on hold to go back and get it.