This is an insulting and derogatory description for somebody who is very, very cheap. It's believed that crab's asses are rather compact, so someone tighter than a crab's ass is about as selfish/cheap/greedy as it gets.
Jake: Bill by the way, what did you leave our waiter?
Bill: 15%.
Jake: Christ Bill you're tighter than a crab's ass. I have to stop eating with you if you're going to embarrass me like that again in public. That poor waiter worked his ass off you cheap fuck.
Bill: 15%.
Jake: Christ Bill you're tighter than a crab's ass. I have to stop eating with you if you're going to embarrass me like that again in public. That poor waiter worked his ass off you cheap fuck.
by Space Wrangler August 24, 2021

The pacific crab is when a man, takes his thumb, sticks it in the ass of a girl and then takes his pointer finger and sticks that in the vagina of the girl. When both fingers are in he then begins to pinch.
by CanadaxUnicorn January 8, 2018

a condom or any protection that helps against getting crabs.
Such as a crab vest that protects you from getting pinched from a crab.
Such as a crab vest that protects you from getting pinched from a crab.
by therocker345 March 15, 2010

by Jelliedbacon206 May 23, 2019

Crab crediting is the act of trading crab (or other expensive meals and delicacies) for sexual favors.
"I heard Dave is a sugar daddy."
"Nah, he just does a lot of crab crediting to get what he wants."
"Oh, well, I guess a girl has to eat!"
"Jane, you stupid filthy slut, I heard you've been crab crediting at the local Red Lobster again."
"Hey, a girl has to eat!"
"Nah, he just does a lot of crab crediting to get what he wants."
"Oh, well, I guess a girl has to eat!"
"Jane, you stupid filthy slut, I heard you've been crab crediting at the local Red Lobster again."
"Hey, a girl has to eat!"
by Dire_is_dire August 27, 2023

"Bro sometimes words look like they aren't real words" "Oh no bro you got brain crabs" "Oh shit bro"
by albeefo July 14, 2022
