When a man's penis goes from being erect to soft very quickly and continuously so it resembles a turtle sticking its head in and out of its shell continuously.
Girl 1: OMG Tina I put my finger in John's butt last night and he got a Funny Turtle!
Girl 2: He should just make up his mind as to whether or not he likes it.
Girl 2: He should just make up his mind as to whether or not he likes it.
by YAHDOEHADLWA April 18, 2016
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