quadrilateral; quadrangle; tetragon
Technical geometry term for any four-sided polygon. In everyday contexts, 四角形 is more common.
The sum of the interior angles of a quadrilateral is 360 degrees.
This shape is classified as a quadrilateral.
三角形 means triangle; 四辺形 is the four-sided counterpart.
Compound of 四 (four) + 辺 (side) + 形 (shape). A straightforward kanji-based term for a four-sided figure.