Bot
An automated or absent player, and the accusation thrown at anyone who plays like one.
Also known as botting, afk player.
Real bots exist and are banned in waves: accounts left running scripted battles to farm credits, recognisable by driving the same line into the same wall every game.
The word is used far more often as an insult for a teammate who did something inexplicable, which is why the chat calling someone a bot is not evidence of anything.