Dick wagging 

The outrageous and rowdy display of alpha male masculinity in a public setting. A guy talks and brags loudly, waves his arms to exaggerate his size and power and even intimidates other guys and girls in a display of dominance. The behavior can be attractive, but often becomes irritating quickly.

These guys at the bar have been dick wagging all night long. I am tired of their crap, so I'm leaving. obnoxious, cocky,alpha male, bravado, tool, egomaniac, arrogant

Dick wagging by joecoolthefool June 8, 2015

dick waggling contest 

Any event where males try to prove their worth by comparing their (often irrelevant) possessions/attributes, especially when size is involved. Good examples are the comparisons of engine or salary sizes. This meaning originates from the idea that he whose penis is larger is superior; primitive males would 'waggle their dicks' to show whose was bigger.

Reporter: President Johnson, why are we still fighting the war in Vietnam?
LBJ: (unzips his fly, draws out his substantial organ): This is why!
Onlooker 1: Dude, that guy just whipped it out like LBJ! It's like the whole war is just a big dick waggling contest!
Onlooker 2: That IS LBJ, fool.

dick waggling contest by Benny Singles December 8, 2007