An object, for example a small firm pillow, placed under a womens ass to elevate her vagina to the best angle for sex.
"Hey honey, lets use the assjack tonight. I want to be sure i hit your G-Spot."
By Kippy
Assjack
Nom. adj -- a person who is hopelessly stupid, offensive or socially hindered in the sense that their very presence has become a blight upon the fabric of existence. (Vulgation of the English "jack-ass," reportedly when the coiner of the phrase was too intoxicated to correctly say "jack-ass."
ass jack; Texan small booster seat used for securing the optimal angle of entry for back-seat-of-the-car sex
"Loren, will you bring that ass jack just a scootch closer so's I can really feel it"
By Paulie
Assjack
When your wallet or phone is so big when you sit down it pick's up one side of your ass or your whole ass a bit higher and make you lean left or right.
My wallet has so much money when I sit down my assjack makes my right ass cheek higher then the other!