永久(えいきゅう)に

えいきゅうに
adverb
permanently; perpetually; for good
formaltime-general
1. permanently; perpetually; for good
Indicates something lasting indefinitely without change or reversal. More factual and formal than 永遠(えいえん)に, often used for official, legal, or scientific permanence.
この記録(きろく)は永久(えいきゅう)に保存(ほぞん)される。
This record will be preserved permanently.
永久(えいきゅう)に使(つか)える保証(ほしょう)はない。
There is no guarantee it will last forever.
あの種(しゅ)は絶滅(ぜつめつ)して、永久(えいきゅう)に地球(ちきゅう)から姿(すがた)を消(け)した。
That species went extinct and disappeared from the Earth for good.
資源(しげん)が永久(えいきゅう)に続(つづ)くわけではない。
Resources will not last forever.

Adverbial form of 永久(えいきゅう) (permanence; eternity) + に. Compared to 永遠(えいえん)に, this word is more objective, factual, and formal. It is preferred in scientific, legal, and official contexts where genuine permanence is at stake.

Common collocations

Similar words

  • 永遠(えいえん)に: forever; eternally — more emotional and literary, used for feelings, memories, and hyperbole
  • 恒久的(こうきゅうてき)に: permanently — formal/official synonym, used in policy and institutional contexts
  • 半永久的(はんえいきゅうてき)に: semi-permanently — indicates very long but not truly infinite duration

Related Words

Compare: 永遠(えいえん)に (forever)
Compare: 恒久的(こうきゅうてき) (permanently)
general
Added 2026.5.8 20:15 · Revised 2026.9.2 13:02
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