“Girl inches” refer to when a girl thinks a guys dick is much bigger than it actually is. This is partly due to guys over exaggerating their size.
So when a girl sees a dick thats around 6 inches, she’ll think its 8 or 9.
Guy 1: I was with amy the other night, she really liked what I was packing

Guy 2: Maybe in girl inches..
by Leftonreplied November 10, 2019
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Girl inches is a measuring unit for the penis that is based on a girl’s perception of the penis rather than the actual length and/or girth of the penis.

Girl inches can be caused by an exaggeration or miscalculation on part of the male who is relaying to the female how large his penis is. It can also be caused by a general ignorance in the literal size of penises on part of the female, and also exaggeration on part of the female to increase the status of the man she is reciprocating with (ie “My man has a bigger dick than your man”).
Paul: My girl said her ex was packing 10 inches

Matt: Oh Zack? He’s barely bigger than me. 7.5 tops. She’s just using girl inches to make you feel bad. She’s TOXIC
by 100PercentEthylAlcohol February 1, 2022
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