事故|じこjiko[1]atamadaka (head-high)

1. nounaccident; incident; trouble
   その事故じこについて彼かれに質問しつもんした。↗

   I asked him about the accident.
2. nouncircumstances; reasons

• SynonymアクシデントNeutralNeutral loanword for an unexpected accident or mishap; can be minor or major, as in 「ちょっとしたアクシデント」 and 「重大なアクシデント」.
• SynonymもしものことCasualColloquial euphemism for 'if the worst should happen', as in 「もしものことがあったら」; often implies death or serious injury.
• Synonym変事へんじWrittenWritten word for a sudden calamity or disaster; has an old-fashioned ring.
• Related異変いへんWrittenWritten word for an abnormal change or strange occurrence; stresses that something is out of the ordinary, as in 「体に異変を感じる」.
• Related急変きゅうへんWrittenWritten word for a rapid change in things like one's condition, the weather, or an attitude; can also mean a sudden emergency, as in 「容体が急変する」.
• Antonym無事故むじこNeutralAntonym of 「事故」: the state of having no accidents occur, as in 「無事故無違反」.

「事故」 is the default for accidents. Use 「アクシデント」 as the loanword (minor or major), 「もしものこと」 as a euphemism for the worst happening, 「異変」 for something abnormal, 「急変」 for a sudden change, 「変事」 for an old-fashioned written calamity; 「無事故」 is the opposite.

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

1. 思おもいがけず起おこった悪わるい出来事できごと。
2. 人ひとの身体からだや物品ぶっぴん、機器きき類るいなどに何なんらかの影響えいきょうが生しょうじるような事態じたい。特とくに交通事故こうつうじこ。
3. 不祥ふしょう事案じあん。
4. 事ことの起おこった理由りゆう。事情じじょう。