A skin-like film which forms on the penis after ejaculation, when the semen dries.
John: Dude! Your dick skin is peeling!

Joe: Oh that?!? No that is my sperm derm. I was masturbating in the kitchen an hour ago.

John: Oh. Okay.... Hey this egg flour soup tastes kinda funny.
by rogerthewhale August 18, 2010
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