背信|はいしんhaishin[0]heiban (flat)
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Definitions
- suru verb, no-adjectivebetrayal; infidelity
Conjugation
| Dictionary form | 背信する（はいしんする） |
|---|---|
| Polite (masu) | 背信します（はいしんします） |
| Negative (nai) | 背信しない（はいしんしない） |
| polite (masen) | 背信しません（はいしんしません） |
| classical zu / nu | 背信せず・背信せぬ（はいしんせず・はいしんせぬ） |
| Past (ta) | 背信した（はいしんした） |
| polite (mashita) | 背信しました（はいしんしました） |
| Past negative (nakatta) | 背信しなかった（はいしんしなかった） |
| polite (masen deshita) | 背信しませんでした（はいしんしませんでした） |
| Te form | 背信して（はいしんして） |
| Potential | 背信できる（はいしんできる） |
| Passive | 背信される（はいしんされる） |
| Causative | 背信させる（はいしんさせる） |
| Causative passive | 背信させられる（はいしんさせられる） |
| Conditional (ba) | 背信すれば（はいしんすれば） |
| tara | 背信したら（はいしんしたら） |
| Volitional | 背信しよう（はいしんしよう） |
| polite (mashou) | 背信しましょう（はいしんしましょう） |
| Imperative | 背信しろ（はいしんしろ） |
Common forms generated by rule; see the senses for honorific or irregular usage.
Synonyms & antonyms
- Synonym裏切りうらぎりNeutralThe everyday word for betrayal, as in 「友の裏切り」; 「背信」 is more written and legal in flavor and stresses breach of faith.
- Related反逆はんぎゃくNeutralRebellion against a regime or one's lord; carries political overtones, while 「背信」 covers any breach of trust, whatever the target.
- Related寝返りねがえりNeutralLiterally rolling over in bed; by extension, going over to the enemy. It stresses switching sides; 「背信」 is breach of faith in general.
- Related異心いしんWrittenWritten word for harboring treacherous intentions; it points to the inner mind, while 「背信」 refers to betrayal already carried out.
- Related内応ないおうWrittenWritten word for secretly conspiring with the enemy from within; 「背信」 covers any breach of trust, not only collusion with the enemy.
- Related内通ないつうWrittenWritten word for secretly communicating with the enemy, or for a secret love affair; 「背信」 is breach of faith in general.
- Related返り忠かえりちゅうWrittenArchaic term for abandoning one's lord and joining the enemy; almost never used today — say 「裏切り」 or 「寝返り」 instead.
- Related逆心ぎゃくしんWrittenDated written word for plotting against one's lord; 「背信」 denotes the act of breaching faith itself.
- Related裏切り行為うらぎりこういNeutralAn act of betrayal or double-cross; fits both speech and writing and is easier to grasp than 「背信」, which leans legal.
- Related背信行為はいしんこういFormalFormal term with the same meaning as 「背信」, naming the concrete act; common in news reports and legal documents.
- Antonym忠誠ちゅうせいNeutralAntonym: unwavering loyalty to a lord or organization, as in 「忠誠を誓う」; the opposite of 「背信」's breach of faith.
- Antonym信義しんぎWrittenWritten antonym: keeping promises and acting with honor, as in 「信義を守る」; the direct opposite of 「背信」.
Use 「背信」 for betraying trust or good faith; it is written, formal and legal, as in 「背信行為」. In daily speech say 「裏切り」; for rebellion against a ruler or regime, 「反逆」; for switching sides, 「寝返り」. The antonym is 「信義」.
Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only
Japanese definitions
Kanji in this word
English equivalents
See also
