周期(しゅうき)

しゅうき
noun
cycle; period; frequency
time-periodscience
1. cycle; period; recurring interval
A fixed interval at which something repeats regularly, used in science, economics, and everyday life for any recurring pattern such as seasons, tides, or business fluctuations.
月(つき)の周期(しゅうき)は約(やく)29.5日(にち)だ。
The cycle of the moon is about 29.5 days.
この現象(げんしょう)は一定(いってい)の周期(しゅうき)で繰(く)り返(かえ)される。
This phenomenon repeats at a fixed cycle.
景気(けいき)には好況(こうきょう)と不況(ふきょう)を繰(く)り返(かえ)す周期(しゅうき)があると言(い)われている。
It is said that the economy has a cycle of alternating between booms and recessions.

Refers to a repeating interval or cycle in which something occurs regularly. Combines 周(しゅう) (circumference, go around) and 期(き) (period, term).

Usage

  • Used in scientific, medical, and general contexts for any recurring pattern
  • Common in discussions of astronomy, biology, economics, and physics
  • Can refer to both natural cycles (seasons, tides) and human-made cycles (business cycles)

Common collocations

Similar words

  • サイクル: cycle — the loanword equivalent, common in casual and business contexts
  • 期間(きかん): period, duration — a span of time, not necessarily repeating
  • 頻度(ひんど): frequency — how often something occurs, rather than the interval itself

Related Words

Compare: 期間(きかん) (period, duration)
Compare: 頻度(ひんど) (frequency)
general
Added 2026.4.3 7:09 · Revised 2026.9.2 13:02
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