Stiffy 

An extended magazine for a firearm.

"You already know I got a Stiffy on this glock"

Stiffy by Kazials February 3, 2018

stiffy 

a person that has a slow working brain and usually dont get things after 1hr-7days

do you have a stiffy????

stiffy by Anonymous October 14, 2003

Stiffy 

Hitting someone hard

Ow you gave me a stiffy

Stiffy by DeathOi March 26, 2021

Stiffy 

An erection. A dick getting hard due to sexual excitement. Hot girls tend to make a guy’s dick all stiffy.

Me: (Watching a Marilyn Monroe documentary film)

My mother: Are you getting all stiffy?
Me: LOL, shut up.

Stiffy by AntiCircumcisionMan May 3, 2021

Stiffy 

Basically a stiff boner

"I have a stiffy"

Stiffy by ImLuckyNotKyle July 28, 2021

stiffy 

A stiffy refers to a new mask

god-dammit dude this mask you gave me is a stiffy.

stiffy by Bofa.d August 1, 2021

stiffy 

What i am right now.

Me: Im so fucking stiffy holy fucking shit
Friend: say less

stiffy by uvuboy446 August 20, 2021