One is longcocked when he has his girlfriend or object of his affection spirited away by someone who might be perceived as more virile.
Longcocked again! You are such a Nancyboy!
1.) Someone with an extra large male reproductive organ
Wow, what a longcock that lad has...
To over rule/win with great confidence. By going over and above, or by possessing a superior idea.
Dan and Tim were fighting over the same girl at the bar. Both went and talked to her but when Tim talked to her had the the waitress bring over her favorite drink. Thous Tim Long Cocked
Dan. She was impressed and went home with Tim.