億おく

お

く

Common wordJLPTN5Freq.FrequencyTop 1,000

Meanings

1

hundred million; 100,000,000; 10^8

The base unit for 100,000,000 in the Japanese counting system. Used in financial, demographic, and large-quantity contexts.

日本にほんの人じん口こうは約やく1いち億おく2000にせん万まん人にんです。

Japan's population is about 120 million.

そのプロジェクトには3さん億おく円えんかかった。

The project cost 300 million yen.

Usage patterns

〈数かず〉億おく円えん... hundred million yen (large sums of money)
この会かい社しゃの年ねん間かん売うり上あげは十じゅう億おく円えんです。
This company's annual sales are one billion yen.
〈数かず〉億おく人にん... hundred million people (population figures)
世せ界かいの人じん口こうは八はち十じゅう億おく人にんを超こえました。
The world's population has exceeded eight billion people.

Kanji

億hundred million, 10**8

Related words

万まんN5
億 means 100,000,000, a much larger unit than 万 (10,000); 1億 equals 10,000万.

Don't confuse with

万まんN5
万 is 10,000 while 億 is 100,000,000, and learners often misplace the four extra zeros when converting between the two.
兆ちょうN1
兆 is 1,000,000,000,000 (the unit above 億), and learners sometimes confuse the two when reading very large numbers aloud.
奥おくN3
奥 (inner depths) and 億 (the number one hundred million) are pronounced identically but have completely unrelated meanings.
百ひゃく万まん
億 means one hundred million (10^8), a unit two orders larger than 百万 (one million), so the two are easy to mix up when reading big numbers.

Etymology

From Middle Chinese 億 (ʔɨk̚). The character originally meant 'to think' or 'a hundred thousand', but in Japanese it was adopted to represent 100,000,000.