The male definition of cockblocker is to sabatoge another guys chance of scoring with a chick.  This concept was foreign to me until going out on occasion with my college roommates friends. 
While one guy was is the bathroom, another guy would tell whatever girl was there things like... its a shame he has been unemployed for 3 years..... rough deal with that restraining order.... he doesn't pay his child support for his 4 kids........he is changing his colostomy bag...it wasn't his fault he caught herpes..... Stuff to that effect.. The girls wouldn't say anything when the guy comes out of the bathroom, the guy of course doesn't score.. then they never even tell the guy that was in the bathroom what they said to the girls.....
Shit is reprehensible..
While one guy was is the bathroom, another guy would tell whatever girl was there things like... its a shame he has been unemployed for 3 years..... rough deal with that restraining order.... he doesn't pay his child support for his 4 kids........he is changing his colostomy bag...it wasn't his fault he caught herpes..... Stuff to that effect.. The girls wouldn't say anything when the guy comes out of the bathroom, the guy of course doesn't score.. then they never even tell the guy that was in the bathroom what they said to the girls.....
Shit is reprehensible..
Steve was a cockblocker when he told the bartender Paul was out on parole when he was in the shitter
by teabag September 25, 2007
 Get the cockblockermug.
Get the cockblockermug. To fully understand the ways of a clockblock, one must set a scenario. Ok, say you've been out all night hanging with this girl, and can sense that you are mere seconds away from going upstairs too hook up with her. Here comes your good buddy cockblock. His drunk, attention-needing self jumps right into the picture and tells your woman how beautiful she is, then throws up all over her. Instead of giving you a quality BJ, she drives old Cockblock home, leaving you by your lonesome to jerk off all night.
Male: You have really pretty eyes.
Female: Do you feel like going---
Lukas: I LOVE YOU!
Male:"Damn cockblock...."
Female: Do you feel like going---
Lukas: I LOVE YOU!
Male:"Damn cockblock...."
by Ruf September 22, 2005
 Get the cockblockmug.
Get the cockblockmug. While I was having sex with my girlfriend, Bob cockblocked me by breaking into my room and throwing a wet paper towel at my face.
by KillaKinz March 1, 2009
 Get the Cockblockedmug.
Get the Cockblockedmug. by blank June 9, 2003
 Get the cockblockermug.
Get the cockblockermug. a person who comes between you and a successful score by continually derailing the train or showing up at the worst times possible with inane, unrelated blather
by kitznegari November 9, 2002
 Get the cockblockmug.
Get the cockblockmug. Got cockblocked by mom last night. Amy said she was ready to go all the way, but she went home instead and I got grounded. I might be a virgin for another week yet.
by MrKapper Is Back December 12, 2012
 Get the cockblockmug.
Get the cockblockmug. i hate you, you fucking cockblocker
by G3orgy100 January 28, 2010
 Get the cockblockermug.
Get the cockblockermug.