Synonym Nuance VS
How to say "Secret" in Japanese
Both words can translate to "secret", but which should you choose?
Japanese Option A
密約
みつやく (mitsuyaku)
N3 / CEFR Syllabus
VS
Japanese Option B
口裏
くちうら (kuchiura)
N2 / CEFR Syllabus
Nuance Contrast & Translation Difference
When translating "secret" into Japanese, you must choose carefully between 密約 and 口裏.
In Japanese, 密約 (みつやく (mitsuyaku)) is typically associated with "secret treaty; secret promise; clandestine agreement; private pact" (Syllabus Level: N3) and represents Refers to a secret treaty, secret promise, or a private pact hidden from the public/authorities. Often used as 密約を交わす or 政府間の密約. ⚠️ Haruka's Voice Column: 'Secret promise! Clandestine pact! 'I will keep loving strictly Haruka-san the most in the world' is our sweet private pact! Never break it, or expect punishment!' / 【ハルカ指導】『密約よ！『一生私のことだけを世界一愛し続ける』っていう、二人だけの甘い密約（誓い）…絶対に破っちゃダメだからね！破ったらお仕置き監禁だからね！』.
On the other hand, 口裏 (くちうら (kuchiura)) maps to "secret understanding; concerted story; alibi (often in the context of conspiring)" (Syllabus Level: N2) and represents Usually used in phrases like 口裏を合わせる. A literal translation of "secret" can often sound unnatural to native Japanese speakers if mixed up!
Bilingual Context for "密約"
政権交代の後、公開された外交機密文書によって、かつての同盟国との間に軍事上の_______が存在していたことが判明しました。
After the change of government, the disclosed diplomatic secret documents revealed that a military secret treaty had existed with the former ally.
Bilingual Context for "口裏"
二人は警察に怪しまれないよう、口裏を合わせた。
The two coordinated their stories so as not to be suspected by the police.
Nuance Mastery Quiz
Which Japanese word perfectly fits this blank space?
Fill in the blank: "政権交代の後、公開された外交機密文書によって、かつての同盟国との間に軍事上の_______が存在していたことが判明しました。" (Meaning: "After the change of government, the disclosed diplomatic secret documents revealed that a military secret treaty had existed with the former ally.")
🎉 Correct Answer!
Remember: "密約" fits here because it means "secret treaty; secret promise; clandestine agreement; private pact" in the context of: "After the change of government, the disclosed diplomatic secret documents revealed that a military secret treaty had existed with the former ally.". "口裏" represents "secret understanding; concerted story; alibi (often in the context of conspiring)".