RBI 

A game for the Nintendo Entertainment System created by Tengen. The most fun two player game of all time, especially if you want to get hammed.

Simanto: Yo man, I'm bored.
GWAR: Want to play some RBI?
Simanto: Dog, you know how to hit my g-spot

RBI by Lord Gold January 11, 2008

RBI 

Really Bad Image.

This is what happens after TMI. Additionally, when you see something really horrible.

Tim: I just saw a dude eat a booger.
Tony: RBI, man.

RBI by Evogq August 24, 2010

RBI 

Rectal Ball Insertion. When a guy manages to get his testicle into a girl's rectum. To this day, there are no reported cases of the RBI.

We were getting bored with our normal routine, so last month I decided to go for RBIs.

It really, really hurt my balls but I got them in there. I'm up to 5 RBIs this season.

RBI by Daz Jenas December 18, 2009

RBI 

When your friend is having trouble getting up to and beyond third base with a somebody, but you do or say something so that they end up having intercourse.

Charlie was having trouble getting to home plate with his girlfriend, but I earned an RBI by getting them both drunk and alone at that party where they finally had sex.

Lisa wanted to have sex with Gary but he was clueless, so I set them up and they went all the way, earning me an RBI.

I earned an RBI when that guy came over and asked me if I had a spare condom so he could make love to his lady for the first time.

RBI by klide-ax November 8, 2007

RBI 

Random Boner Incident.

Andy- "So, I talked to Sadie yesterday in math class."
Brad- "Did she give you a RBI? That girl is smoking hot!"

RBI by HOG2331 September 8, 2010

RBI 

Random
Bar
Injury

Injury most likely sustained the previous night at a bar, but you were too intoxicated to remember the incident.

waking up in the morning - "where'd that bruise on your face come from?"

"OH, that, must be a RBI"

or

"man my leg hurts, must have gotten a RBI last night"

RBI by Glory Days Girl November 30, 2009

RBI 

Stands for Roast Beef Insertion. It indicates any type of penetration or sexual act.

Also: Baseball. Runs Batted In.

-Ayo, you see Trina?
-Did I see her? I musta got like 4 RBI last night!

RBI by legab April 29, 2009