Definitions by YouOne_

Teamstack 

When an entire team in an video game all unanimously decides to go in the exact same direction or to the exact same spot.
This normally results in said entire team dying in a pathetic way, and looking really stupid.

Can also be used to refer to group of people that have done this.

Random nerd 1: "Yo bro, wanna teamstack left this game?"
Random slightly less of a nerd 2: "Aight"

Both precede to die to a grenade thrown from around a corner (they did this every round).

There is a teamstack of red guys on the right hand side of the map.

Teamstack by YouOne_ May 3, 2023