Clothes women wear when they go out to the club or a party. Can usually be found at your local "Forever 21" store. Can sometimes can be mistaken as a synonym for "slutty attire". Makes most men lose their mind when they see a woman wearing one. Can also usually lead a man to buying a girl a drink at a club. Typically, women who wear it end up grinding some dude on the dancefloor in the club, hence the term.
"Hey girl! You can make a grown man cry with that grinding gear you got on. Let me buy you a drink!"
"Check out that chick by the bar. DAAAAMMMN! That grinding gear is complementing everything her momma gave her!"
"Girl, we going clubbin' tonight! Put on your best grinding gear and get ready to party!"