What does 一旦 mean in Chinese?

一旦 (yī dàn) means "in case (sth happens); if; once (sth happens, then...); when; in a short time; in one day" in Chinese. The new HSK exam tests it at HSK 5.

How do you pronounce 一旦?

一旦 is pronounced "yī dàn" in Mandarin Chinese. It is made up of 2 syllables.

What HSK level is 一旦?

一旦 is an HSK 5 word on the new HSK exam syllabus. It is HSK 5 on both the old and the new exam.

What characters make up 一旦?

一旦 is made up of the characters 一, 旦. Each character has its own meaning and can appear in other words.

How do you write 一旦?

You can practice writing 一旦 using our stroke order tool.

一旦 (yī dàn), in case (sth happens)

一旦

yī dàn

in case (sth happens); if; once (sth happens, then...); when

HSK 5

Characters in This Word

一旦

Definitions

in case (sth happens)
if
once (sth happens, then...)
when
in a short time
in one day

Example Sentences

一旦下雨，比赛就取消。

Yídàn xiàyǔ, bǐsài jiu qǔxiāo

Once it rains, the match is cancelled

Related Words

一不做，二不休(yī bù zuò , èr bù xiū)· don't do it, or don't rest (idiom); either give up, or go through to the end

→

便人(biàn rén)· sb who happens to be on hand for an errand

→

HSK levels

New HSK exam: HSK 5
HSK 2.0: HSK 5
HSK Lord study list: HSK 5 list

一旦: HSK 5 on both the old and the new exam. See where your old level lands

New exam levels follow the CLEC syllabus released 15 November 2025. The first official sitting is announced for 13 December 2026. HSK 7-9 is one advanced band.

On the new HSK 5 exam

Studying for HSK 5? Keep 一旦 with the rest of your level.

HSK Lord schedules your reviews so each word comes back right before you would forget it. Free to start, and it picks up where you are.

Start studying free The words new HSK 5 adds

Frequently Asked Questions

Reviewed by RJ Murray, Founder, HSK Lord.