A rectal speedboat is where your partner is in the bath, you run in hover your anus just in the water and let out a ripper fart, the sound that follows sounds like a backfiring speedboat engine
Oh my partner ruined my bath last night and gave me the rectal speedboat

I’ve been victim to a rectal speedboat
by Siege of Society December 13, 2018
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The action of eating a girl out underwater making a ton of bubbles
He Jeff how did your girlfriend react after you speedboated her ?
She loved it she squirted after I was finished
by OGMUDBONE69 February 28, 2015
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