the Fonz's version of "piss off" or "screw you" and countless other negatory response variations.
(really kinda racey for it's time)

i never really thought about what it literally meant when i was like 5 yrs old. but seeing the reruns now i'm like OMG WTF?!?!? does he really want everyone to sit on his... um, motorcycle? heheh.

Micro marriging is when your partner manages your personal day-to-day tasks with you much like a Micro Manager at work.

to hold for an extended period of time.

Sit on it is what a guy says to another dude when he wants that guy to ride the peg - his big raging boner.

Used as a phrase.

It means to sit somewhere and think about the idea you have or to shut up and think more about what you are going to say before you move on to what you're going to say.

1. What a teacher tells you to do when you excessively sharpen your pencil, blow your nose or go to the bathroom.

2. What you tell someone when they flip you off.

Used in reference to sitting on something in a sexual manner. The phrase first came into being during an episode of "The Girls Next Door" when Hef's new twin girlfriends were doing a sexy tennis photo-shoot. Both were holding tennis racquets and the photographer asked them to do something different. One person who was watching the show shouted, "Sit on it!" in reference to the girls sitting on the tennis racquets in a sexual manner.