心外|しんがいshingai[0]heiban (flat)

1. na-adjective, nounregrettable; vexing; upsetting
2. na-adjective, noununthinkable; wholly unexpected

• Synonym思いがけないおもいがけないNeutralRefers to what you did not foresee, as in 「思いがけない再会」. Neutral and can carry pleasant surprise, whereas 「心外」 carries the displeasure of being misunderstood.
• Synonym意外いがいNeutralThe most widely used word for the unexpected; expresses only surprise, without the hurt or resentment implied by 「心外」.
• Synonym予想外よそうがいNeutralMeans beyond what was predicted, as in 「予想外の結果」; stresses an expectation objectively falling through, with no sense of grievance.
• Synonym意想外いそうがいWrittenMeans unexpected or not foreseen; a written, fairly rare word, and unlike 「心外」 it carries no note of displeasure.
• Synonym存外ぞんがいNeutralMostly an adverb meaning contrary to expectation, as in 「存外簡単」; it also has a rarer sense of rude or insolent.
• Synonym思いもよらないおもいもよらないNeutralAn idiomatic phrase for something you would never even dream of; stronger than 「意外」, and neutral in tone.
• Synonym思わぬおもわぬNeutralA pre-noun adjective meaning unexpected, as in 「思わぬ事故」; often introduces an unwanted or negative outcome.
• Synonym予期しないよきしないNeutralMeans not anticipated; a descriptive phrase that leans technical and suits formal writing.
• Related驚くべきおどろくべきNeutralA noun-modifying expression meaning astonishing, as in 「驚くべき事実」; it stresses the degree of shock rather than any upset.

Use 「心外」 when you feel upset or wronged—misunderstood, treated unfairly, or stung by an off-target remark or a disappointing result, as in 「そう思われるとは心外だ」. For plain surprise pick 「意外」 or 「予想外」; for something you never saw coming, 「思いがけない」.

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

1. （しんがい）思いの外おもいのほか。意外いがい。また的外まとはずれな批判的ひはんてき言辞げんじや迷惑めいわくな行動こうどう、残念ざんねんな結果けっかなどに不服ふふくを感かんじること。
2. （しんがい）心臓しんぞうの外部がいぶ。