In videogames, it refers to the action of trying to get closer to the enemy in order to kill them, with little or none regard for taking cover from enemy attacks.
Example:
*Squad of players spots another squad*
Player 1: Guys lets play this safely-
Player 2: RUSH
*Player 2 gets gunned immediately*
Player 2: bro revive
*Squad of players spots another squad*
Player 1: Guys lets play this safely-
Player 2: RUSH
*Player 2 gets gunned immediately*
Player 2: bro revive
by TheAccelerator September 06, 2019