• 丸まるい — round
• 丸まるごと — whole / entirely
• 丸太まるた — log / timber
• 丸薬がんやく — pill
• 弾丸だんがん — bullet
• 一丸いちがん — one united body
• 丸裸まるはだか — stark naked / completely exposed
• 丸まるめる — to make round; to roll up

This character conveys both “roundness” and “wholeness.” You’ll see it in simple shape words like 丸 まる い, and also in expressions like 丸まるごと — meaning “entirely” or “as a whole.”