期

A phono-semantic compound:

月 (moon) – indicating time (through the phases of the moon)

其 (그 기) – providing the sound.

The original sense is “a determined time marked by cycles”, especially lunar ones.

In bronze inscriptions (金文 jinwen), the combination 其 + 日 (sun) was common.

After the seal script (篆書 zhuànshū) period, 日 was replaced with 月 (moon).

Because the sun and the moon are the brightest celestial bodies in the sky and their positions and appearances change cyclically with time and seasons, ancient people used them to track time.

Semantic development:

Fixed time → promise → 期約 (appointment)

Fixed time → anticipation → 期待 (expectation)

Fixed time → measurable span → 期間 (period)

This semantic expansion is logical and continuous, not metaphorical.

Today, 期 remains central in words about timeframes, promises, and expectations, all rooted in the ancient practice of watching the sun and moon to measure time.

Words with meaning related to time and scheduling:

期間 (기간) – period; term

기한 (期限) — time limit; deadline

시기 (時期) — time; season; phase

정기 (定期) — regular; periodic

주기 (週期) – a cycle or recurring period

단기 (短期) — short term

장기 (長期) — long term

학기 (學期) — school term

임기 (任期) — term of office

And because setting a time allows for making appointments and promises, it also gained meanings like:

기약 (期約) — promise; appointment

기대 (期待) — expectation; anticipation

期 often carries a normative sense, failing to meet a 期 can imply loss of trust.

Unlike 時, which marks time as it flows, 期 marks time as agreed or awaited.

In Classical Chinese, 期 is closely tied to ethical responsibility.

《論語》 (The Analects):

「後會有期。」

“We shall meet again; there is a set time.”

《左傳》 (Zuo Zhuan):

「期而不至，失信也。」

“To fail to arrive at the appointed time is to lose trust.”

These examples show 期 as a morally binding promise of time, not merely a neutral date.