十亿分之一 (shí yì fēn zhī yī) — one billionth (1/1,000,000,000)

Definition

Literally 'one part in a billion' (1/1,000,000,000). Used in science and statistics for extremely tiny quantities or probabilities — not for everyday measurement.

numeral
one billionth (1/1,000,000,000)

Examples

  • 十亿分之一。
    Zhè zhǒng huà xué wù zhì de nóng dù zhǐ yǒu shí yì fēn zhī yī.
    The concentration of this chemical is only one billionth.
  • 十亿分之一。
    Tā zhōng cǎi piào de gài lǜ bú dào shí yì fēn zhī yī.
    His chance of winning the lottery is less than one in a billion.
  • 十亿分之一。
    Kē xué jiā cè liáng dào shí yì fēn zhī yī miǎo de shí jiān biàn huà.
    Scientists measured a time change of one billionth of a second.

Origin

Characters in this word

An abstract idea shown by a mark or a diagram rather than by a picture of an object.

The early shape 十 was mostly a single vertical stroke, sometimes with a dot, and later gained a horizontal stroke to form a cross. For the number ten, it marked the next digit above one.

Open 十 →

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
人人rén
Sound part声符shēngfú
意
意yì億yì
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.

Open 亿 →

Two or more meaningful parts placed together so that their meanings combine into a new one.

分 pairs 八 (to separate) with 刀 (knife), showing something cut apart with a knife.

Open 分 →

Two or more meaningful parts placed together so that their meanings combine into a new one.

The shape pairs 止, a foot, with 一, a beginning place, and means to go.

Open 之 →

An abstract idea shown by a mark or a diagram rather than by a picture of an object.

一 is drawn as one horizontal stroke, marking the number one.

Open 一 →

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