cockblocking

Slang. When one male makes it difficult for another male to get to know a certain female for the purposes of sexual relations, this is known as cockblocking. The allusion here should be fairly obvious.

One who engages in cockblocking can be a "friend" of the female's, or just some guy in the club/party making it more difficult for the one being cockblocked to engage in sexual relations with the female in question. One cannot be cockblocked by a boyfriend or someone who is otherwise romantically involved with the female in question, though someone may cockblock you to "save" the female from cheating on her significant other, who is not present.

When a male is making advances on a female and one of the female's friends (usually female) separates the female and the male to end any chance of him "making a move." The friend usually moves the female away from the man and prevents any conversation from continuing. The friend feels that the female is too inebriated to make good decisions and has decided to make decisions for her. The termination of all conversation and contact with the female eliminates any chance of sexual intercourse with the male. Thus the cock has been blocked.

Cockblocking can be in response to fearing for the female's safety or by jealousy.

To prevent cockblocking a male may recruit a buddy to serve as wingman and distract the cockblocker.