noun

an activity that one engages in for amusement or fun.

the kids were playing a game with their balloons

pastime,diversion,entertainment,amusement,distraction,divertissement,recreation,sport,activity,leisure activity,frolic,romp,source of fun

verb

manipulate (a situation), typically in a way that is unfair or unscrupulous.

it was very easy for a few big companies to game the system