尺子
chǐ zi · HSK 4
rule
📏 尺子 = chǐ (chi, unit of length ~33cm) + zi (noun suffix)
尺 is an old Chinese unit of length (about a third of a metre) and by extension any measuring stick. Adding the neutral-tone 子 suffix turns it into the everyday noun for a ruler.
尺 — pictograph of a hand measuring length
尺 originally depicted a hand stretched out to measure, representing a unit of length. It became the standard Chinese 'foot' (about 1/3 meter today). The character now means a ruler or the length unit 'chi'.
子 — pictograph of a baby/child with arms out
子 began as a pictograph of a swaddled infant with a large head and outstretched arms, originally meaning 'baby' or 'child.' From there it broadened to 'son,' 'offspring,' and a respectful suffix for masters like 孔子 (Confucius). It also became one of the twelve earthly branches.