立方

• Pinyin: lì fāng
• Hanzi breakdown: 立 = 立 (to stand/upright); 方 = 方 (square/direction)

Meaning

Cube; cubic. In mathematics, the result of raising a number to the third power; in geometry, a three-dimensional solid with equal sides.

Used in mathematics (三的立方 = 3³ = 27), physics, and geometry. Can refer to the operation itself (cubing a number) or the resulting solid shape. Also used as a prefix for cubic units of measurement such as 立方米 and 立方厘米.

Examples

1. 在数学课上，老师要求学生计算各正整数的立方值。 In math class, the teacher asked students to calculate the cubes of various positive integers.
2. 这个水箱的容量是八立方，足以满足整栋楼一天的用水需求。 This water tank has a capacity of eight cubic meters, enough to meet the building’s daily water needs.
3. 几何题要求学生推导出各种规则立方体的表面积公式。 The geometry problem asked students to derive the surface-area formula for different regular cubes.

Usage Guide

Context: mathematics, geometry, engineering, measurement

Tone: neutral

Do Say

• 请计算边长为五厘米的正方体的体积，即五的立方。(Please calculate the volume of a cube with a side length of 5 centimetres, which is 5 cubed.)
• 这批木材共运来二十立方，已全部卸载至仓库待用。(Twenty cubic metres of timber were delivered in this batch and have all been unloaded to the warehouse.)

Don't Say

• 将'立方'等同于'正方形' — 立方是三维概念（体积），而正方形是二维图形（面积），二者维度不同，不可混用

Origin & History

立 (upright/standing in three dimensions) + 方 (square) — a square standing upright, implying three-dimensional extension

Cultural Context

Generation: All ages

Social background: Universal