also: まるカッコ · まるがっこ
noun
parentheses; round brackets
Refers specifically to round parentheses ( ) as opposed to other bracket types like 角括弧 [ ] or 波括弧 { }.
補足説明は丸括弧で囲んでください。
Please enclose supplementary explanations in parentheses.
この文の丸括弧の中の数字は注釈番号です。
The numbers in parentheses in this sentence are footnote numbers.
Compound of 丸 (round) + 括弧 (brackets). The reading まるかっこ is standard; まるがっこ is a rare rendaku variant.