天災|てんさいtensai[0]heiban (flat)

1. nounnatural disaster; natural calamity; act of God
   地震じしんや洪水こうずいは天災てんさいです。↗

   Earthquakes and floods are natural disasters.

• Synonym災いわざわいNeutralA neutral word for calamity or misfortune, as in 「口は災いの元」. Broader than 「天災」: it covers troubles of any kind, not just natural disasters.
• Synonym天変地異てんぺんちいWrittenA written word for cataclysms — extraordinary natural upheavals such as earthquakes and volcanic eruptions. It stresses the natural anomalies themselves.
• Related惨事さんじWrittenWritten style for a tragedy or major accident, as in 「大惨事」. It stresses the horrific outcome and covers both natural and man-made events.
• Related惨禍さんかWrittenA written word for grievous calamity, as in 「戦争の惨禍」. It leans toward disasters like war rather than natural events.
• RelatedカタストロフィーWrittenA written loanword for a catastrophe — dramatic destruction or a tragic end. Unlike 「天災」, it is not limited to natural disasters.
• Related変災へんさいWrittenWritten style for an unexpected disaster or accident; rare in modern Japanese.
• Related大難だいなんWrittenWritten style for a great disaster or calamity; rare in modern Japanese.
• Related大災たいさいWrittenWritten style for a great disaster; rare in modern Japanese.
• Antonym人災じんさいNeutralThe antonym: a calamity caused by human error or negligence, as in 「天災ではなく人災だ」. It contrasts directly with naturally caused 「天災」.

Use 「天災」 for natural disasters like earthquakes and typhoons, as in 「天災は忘れた頃にやってくる」. For man-made calamities say 「人災」, for horrific tragedies 「惨事」, for cataclysmic natural upheavals 「天変地異」. 「災い」 covers misfortune broadly; 「カタストロフィー」 and 「惨禍」 are written words for catastrophe; 「変災」「大難」「大災」 are rare today.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 地震じしんや洪水こうずいなど、自然しぜん現象げんしょうが引き起ひきおこす災害さいがい。自然しぜん災害さいがい。