Mangina or Man-gina would be gay slang for anus, ass or man-cunt. Often used on the leather scene but on the whole it is a generic term for a guy's butt hole.
An illusion where a man "tucks his stuff" (i.e., hides his genitalia between his legs) thereby giving his pubic region the apperance of that of a female's.
The insane popularity of this trick is usually traced to (credited to or blamed on) the 1991 Jonathan Demme movie "The Silence of the Lambs"
"I saw a man-gina contest on spring break in mexico ... they had 5 drunk guys tuck in their stuff and drop trouon stage."
The correct pronunciation of the New York Jets Coach Eric Mangini's last name. After being a NE Patriots coach, he is now whining about how the Pats' coaches analyze the competition.