referring to an event when two people of the opposite sex (in some cases there are exceptions) start grinding in a public place, when they infact, SHOULD NOT BE. most likely, everyone is staring at them because they are weird not because they think they are a cut couple.
megan: "ewww me god we survived the grindage!"
caroline: "ohh emm gee we should make shirts!"
A cash game of poker, reffered to grindament's by top players as this due to the general method used to beat these games is to play only premium hands as the blinds do not increase and the game never ends.
"playing the stars 100R tonight bro?"
"Nah prolly gonna hit the grindaments"