Translation guide
In Japanese, the word for 'rectangle' is 長方形 (ちょうほうけい). However, in everyday conversation, people often use 四角 (しかく), which broadly means 'square' or 'quadrilateral'. This guide explains how to express 'rectangle' naturally depending on context.
Referring to a shape with four right angles and opposite sides equal, in mathematical or precise contexts.
The standard mathematical term for 'rectangle'. Used in textbooks, geometry, and formal descriptions.
This shape is a rectangle.
A more technical or formal term for 'rectangle', often used in mathematics or engineering. Less common in daily speech.
Calculate the area of the rectangle.
Describing something rectangular in shape, like a table, box, or piece of paper, in casual conversation.
Literally 'four corners', this is the most common way to say 'rectangle' or 'square' in daily life. It can refer to any quadrilateral, but context usually clarifies the shape. To be specific, you can add 長い (ながい, 'long') or describe the proportions.
That table is rectangular in shape.
A colloquial term combining 長い (long) and 四角 (square), explicitly meaning 'oblong' or 'rectangle'. Used when you need to distinguish from a square.
Describing something as 'rectangular'.
四角 (しかく) is the everyday word for any four-sided shape, including squares and rectangles. 長方形 (ちょうほうけい) specifically means 'rectangle' in a mathematical sense. Use 四角 in casual conversation unless precision is required.
The adjective 四角い (しかくい) is very common and can mean either 'square' or 'rectangular'. If you need to emphasize that something is not square, you can say 細長い四角 (ほそながいしかく, 'long and narrow rectangle') or 長方形 (ちょうほうけい).
Please give me a rectangular box.
この紙は長四角に切ってください。
Please cut this paper into a rectangle.
While primarily a geometric term, it can be used in everyday contexts when precision is needed, such as describing the shape of a room or object.
This room is rectangular.