虚数 (xū shù) — (mathematics) imaginary number; (figurative) un…

Definition

In math, an imaginary number (one whose square is negative, like i). Figuratively, a fabricated or untrustworthy figure — e.g. fake data in a report.

noun

(mathematics) imaginary number(figurative) unreliable figurefabricated number

，虚数。
Zài shù xué zhōng, xū shù shì píng fāng hòu wèi fù shù de shù.
In mathematics, an imaginary number is a number that becomes negative when squared.
虚数，。
Tā bào gào lǐ de shù jù quán shì xū shù, bù néng xiāng xìn.
The data in his report are all imaginary numbers — can't be trusted.
虚数。
Fù shù yóu shí shù hé xū shù zǔ chéng.
Complex numbers consist of real numbers and imaginary numbers.

Compound word

构词法gòucífǎ

偏正piānzhèngModifier + head

The first part narrows down the second: it says what kind of thing the head is.

虚xūempty or false

虚 gives false or imaginary and 数 gives number; together they name an imaginary number or fabricated figure.

Characters in this word

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

This origin belongs to the traditional form 虛; 虚 is its simplified writing.

Meaning part形符xíngfú

Sound part声符shēngfú

虍

虍hū虛xū

Close in sound todayThe sound part was a clue two thousand years ago — it often still helps, but not always.

The traditional form 虛 pairs the upper 虍, which gives the sound, with a lower part shaped like 丘, 'hill'; the simplified 虚 is a later shorthand.

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

This origin belongs to the traditional form 數; 数 is its simplified writing.

Meaning part形符xíngfú

攴攴pū

Sound part声符shēngfú

婁

婁lóu數shù(r)

The sound has drifted apartThe sound part was a clue two thousand years ago — it often still helps, but not always.

The traditional form 數 pairs 攴, the meaning part, with 婁, the sound part; the simplified 数 is a shorthand.