The act of masturbating to a girl (or guy) from your past who at one point was extremely attractive but is no longer due to aging or weight gain. The masturbator would then jerk off to a mental image of how the once attractive girl looked in the past (retroactively) rather than how she looks currently. This occurs quite often when thinking about aging female celebrities who at point were major sex symbols.

Similar to "nostalgia wank".
Rick: Yo man, did you see Chloë at our ten year high school reunion?

Matt: Yea, brah. She got fat. Fuckin' shame, she used to be sooooo hot.

Rick: I know right? I'm gonna find an old yearbook and beat off to the way she used to look in high school.

Matt: Good ol' retroactive masturbation! Ya know, for a quicker yank, you could just scroll backwards through her Facebook profile photos.
by jodielover81 October 4, 2018
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