1.
square pyramid; quadrilateral pyramid
A pyramid with a quadrilateral base (typically a square or rectangle) and four triangular faces meeting at an apex. A standard solid figure introduced in middle-school geometry, familiar as the shape of the Pyramids of Giza.
The volume of a square pyramid is found by multiplying the base area by the height and dividing by three.
Composed of 四角 (quadrilateral, square) and 錐 (cone, pointed solid). The suffix 錐 is used productively in geometric terms for pyramids and cones.
Usage
A technical term in geometry, appearing mainly in math textbooks, lesson materials, and science writing. Like most Japanese geometric-solid names, it is formed with a base-shape name plus 錐.
Common collocations
- 四角錐の体積: volume of a square pyramid
- 四角錐の表面積: surface area of a square pyramid
- 四角錐の展開図: net (unfolded diagram) of a square pyramid
- 正四角錐: right square pyramid (with a square base and apex directly above the center)