When a gathering suddenly accumulates more men than woman to a significant degree. A man to female ratio of a least six men to every one female constitutes an official broverflow.
The overwhelming sensation one gets when surrounded by too many bros (young men generally characterized by open shirts, spiked hair, mixed drinks, and extreme self-confidence).
"O.A.R. is like my favorite band!"
"Did you get that shirt from American Eagle? Awesome, bro!"
"I love playing John Mayer songs on my guitar. That bro knows how to play."
Sneering at the Phish poster on the wall, you say to your friends "This party is broverloaded. Let's bail."
Chronic use of the word "bro" in a situation or setting. Many times resulting in the annoying of other individuals said situation or setting. Can also be define as the over use of the word bro in any general sense.