Top Definition
Derived from the term 'bandwagon', it's used to collectively describe girls who back up one of their own for sometimes no valid reason other than sharing gender. 'On the Jam' is a vernacular phrase for being on ones period.
Bert: Kate told Donald she was on her period and couldn't have sex. Donald, hearing this, told her he didn't want her to stay over that night and left. Ellen called Donald a dickhead after Kate telling her this.
Ernie: Ellen jumped on the Jamwagon.Surprise Surprise
by Short and Curleys February 18, 2011

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A sexual activity involving two men and a woman. One man engages in anal sex with the woman while the second man anals the first man, all simultaneously. One or more women are free to engage in the action.
Jim:I'll put it in your ass Tanya.

Tanya: okay papa, give it to me.

Bill: Now stay calm Jim, I'm gonna slide it in there.

Jim: Great, this'll be a fine jamwagon.

(All partake in an anal demolition)
by Ethantyrobi February 17, 2017

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One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

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Soft and offensive. Just like you.

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The Urban Dictionary T-Shirt

Smooth, soft, slim fit American Apparel shirt. Custom printed. 100% fine jersey cotton, except for heather grey (90% cotton).

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