What is Roundabout?
1.
A form of sexual activity, more specificly handjob, where the female places the males penis in the palm of her left hand. The female then proceeds to violently bash the top of the penis with her right elbow, until the male orgasms.
"Dude I'm still sore from where Katie gave me a roundabout last night"
"Awesome"
See
2.
A Roundabout is a sexual act which involves at least 4 men, whereby each person is and has a hole filled, thus creating the Roundabout effect.
Mike: Hey Jimmy what did you do last night?
Jimmy: Eh, nothin much Bryson and some of his friends came over last night.
Mike: Oh, is that the dude with Münchhausen's?, anyway so what happened last night?
Jimmy: We done this thing called a Roundabout, it was awesome.
Mike: Dude, thats sick.
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3.
A fight or argument that never escelates to curse words or physical contact; Never results in hurt feelings or death.
The cold-war between the U.S. and Russia could be considered a roundabout.