noun which may take the genitive case particle 'no', na-adjective, noun
square; perfectly square
Emphasizes a shape that is exactly or unmistakably square, often with a sense of being rigidly or neatly square. The prefix 真っ adds intensity.
See also: 真四角
彼は紙をまっ四角に切った。
He cut the paper into a perfect square.
その箱はまっ四角で、角がきっちりしている。
The box is perfectly square, with sharp corners.
Formed by attaching the intensifying prefix 真っ (ma-) to 四角 (shikaku, 'square'), with gemination for emphasis. The resulting form means 'perfectly square'.