If something is marred, it’s damaged due to a flaw. If the big football game on Sunday ends with a fight among fans of the opposing teams, commentators will say that the game was marred by violence.
The word marred can be traced back to the Old English word merran, meaning “to waste or spoil.” Marred often carries with it the sense of spoiling perfection. It can be a flaw that makes something outstanding less than perfect, such as a movie star’s face marred by a scar or a career marred by controversy.