Definition of "scumming"

(printing) The accumulation of sticky ink on a plate.  examples

(chiefly in the plural) That which is scummed off; skimmings; scum.  examples

(video games, derogatory) The strategy of collecting easy rewards in unchallenging areas, e.g. when a high-level character visits levels suitable for low-level characters in roguelike games.  examples

(video games, derogatory) The act of restoring a game's save file, or restarting the game, for the purpose of continuing play with a better outcome than was obtained the first time.  examples