“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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A covert technique used by men during sex when you reach behind and pulls your ball sac back and away from your body; this action enables your penis to extend forward hence revealing your hidden penile inch. Most effective on women you fuck for the first time and during doggy style when your partner is unaware of your activity.
I fucked my girl good last night, I gave her the hidden inch!

That bitch thinks I have a big dick but I fooled her with my hidden inch!
by steelerstevo April 21, 2015
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noun. an ironic alternative of interesting. the term comes from the mispronunciation.
by daturana May 29, 2018
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The amount of the penile shaft that is hidden by a fully grown out pubic bush.
Guy 1: “man, my dick is not looking too impressive today... I hope she thinks I’m big enough...”
Guy 2: “make sure you’re clean shaven! You’ll gain access to the secret inch!”
Guy 1: *shaves* “Woah! Now you can see all two inches!”
by peeemthreek July 20, 2018
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The extra inch of length a shaved penis appears to have over an unshaved one.
The optical inch my shaved cock has makes it look bigger.
by jer_ May 04, 2006
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When a big dick meets a not so big vagina. It's not how much got in but how much was left dry in the wind, never getting wet.
Joe: How did it go last night with the skank you met?
Jim: Well it went ok I guess. I still had about 4 dry inches to go when she said it hurt.
Joe: Man 4 dry? that sucks dude.
by Jumpingrat October 31, 2010
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