Kill-Death Ratio is a term used to define how many kills a player gets before they die each time they spawn. A K/D ratio is kills divided by deaths. For example, if a player gets 10 kills and 5 deaths in a given game, they have a 2 K/D ratio. It means they got 2 kills before they died each time they spawned (on average). In other words - for every 2 kills they got, they died once.