Closely related to the cock-block (cockus-blockus). Occurs when you are trying to solidify a possible sexual encounter, only to be stifled by either the conscious or inadvertant action of a third party. Quite often, the offending third party is a friend who wants to subvert your sexual activity.
I was at a party last week dancing with this really cool girl, when all of a sudden out of the corner of my eye I saw Steve coming in for the kill. Steve got in between this girl and myself and started telling her I had a girlfriend, even though I don't. He also told her that I was a born-again Christian, and she shouldn't be tempting me with her sex. It was at that moment I realized Steve had served me up a clinical case of coitus avoidus.
by B-1368 August 3, 2011