五亿 (wǔ yì) — five hundred million (500,000,000)

Definition

numeral

five hundred million (500,000,000)

，五亿。
Zhōng guó yǒu chāo guò shí sì yì rén kǒu, qí zhōng nóng cūn rén kǒu dà yuē wǔ yì.
China has over 1.4 billion people, of which the rural population is about 500 million.
五亿。
Zhè ge xiàng mù de zǒng tóu zī é dá dào le wǔ yì rén mín bì.
The total investment in this project reached 500 million RMB.
五亿。
Dì qiú dào yuè qiú de jù lí dà yuē shì sān shí bā wǔ yì mǐ.
The distance from the Earth to the Moon is about 38.5 million meters.

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.

亿yìhundred million

五 'five' before 亿 'hundred million' gives five hundred million.

Characters in this word

A drawing of the thing itself, worn down over three thousand years into a few strokes.

An older form had a crossed mark between a top bar and a bottom bar. The modern 五 keeps those bars, while the original idea is uncertain.

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 億; 亿 is its simplified writing.

Meaning part形符xíngfú

Sound part声符shēngfú

意

Same sound today

The traditional form 億 pairs 人 (person) with 意 for its sound; the simplified 亿 is a later shorthand, so its parts are not the original pieces.