The wrinkly skin that separates the scrotum into the left and right hemispheres.
I was freeballing and my zipper caught my ballseam.
by mr.krinklebein May 13, 2010
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The line where the two halves of skin join on a scrotum
I love the way your ballseam runs up to the base of your penis splitting your balls between left and right
by HornyBi January 18, 2019
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