The Japaneese word for "circle".
The maru is the equivalent of a check mark; it indicates correct answers, decisions, etc.
The opposite is batsu
, or "X".
If you want to draw Kirby
, you need to start with a maru.
In Kirby's Dream Land 3, you need to get a maru three times to pass the minigames. If you make a mistake, you'll get a batsu