A person who, sometimes repeatedly prevents someone from having any chance of getting laid.
This can be intentional, or an unintentional cock block.

The cock blocker manifests themselves in many forms. Shape Shifters some say.
Some examples are:

Friends, roommates, children, or in-laws
"My daughter has been sleeping in my wife's and I's room allot lately.
She's still little, and doesn't realize the cock block she is"
by Skisonice October 1, 2022
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when ERIK doesnt wanna stop watching fight club
erik pls go home, you are cock blocking

“no i wanna watch fight club
by Tpwk ppl August 8, 2022
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To prevent someone or yourself from preforming any acts sexually with someone of the same or opposite sex, purposeful or otherwise.
Some random woman started flirting with me at the bar, even though I'm happy married. I decided to Cock Block myself to prevent further action.
by JustLeaveMeAlone August 21, 2021
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A person that comes between you and your boyfriend/girlfriend
I kept tryna talk to my girl but Maria kept being a cock block
by Rere272728 April 25, 2019
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When you kill an individual by putting your cock down their throat and block the air way, while covering the nostrils with your nut-sack
Friend 1- How did John finally get rid of that bitchy girlfriend?
Friend 2- I heard he Cock Blocked her
by Pineapple Plug April 21, 2018
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A Cock Block is some who is a compete cunt but also blocks you out
You're being a complete Cock Block today Harry
by ovlavla March 31, 2016
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