一

• Pinyin: yī
• Hanzi breakdown: 一 — a single horizontal stroke representing the number one; a purely ideographic character

Meaning

One; a/an. The number one, also used as an indefinite article equivalent in some contexts.

One of the most fundamental characters in Chinese. Used in counting, measure word phrases, and idiomatic expressions. Its tone changes based on context: 4th tone before 1st/2nd/3rd tone syllables, 2nd tone before 4th tone syllables, and 1st tone in isolation or ordinal usage.

Examples

1. 我有一只猫。 I have one cat.
2. 请给我一杯咖啡。 Please give me a cup of coffee.
3. 一加一等于二。 One plus one equals two.

Usage Guide

Context: everyday, counting, math

Tone: neutral

Do Say

• 我要一个。(I want one.)
• 他有一个妹妹。(He has one younger sister.)

Don't Say

• 注意'一'在不同声调前变调。(Be aware of tone sandhi: 一 changes tone depending on the following syllable — don't always read it as first tone)

Origin & History

一 is one of the oldest Chinese characters, represented in oracle bone script as a single horizontal stroke. It has remained unchanged for over three thousand years.

Cultural Context

Generation: All ages

Social background: Universal