Translation guide
How to express 'keep secret' in Japanese, from casual to formal, including warnings about literal translations.
Please keep it a secret.
The general act of keeping information hidden from others.
The most common and neutral way to say 'keep something secret'. Literally 'make into a secret'.
Please keep this a secret.
He kept the plan secret.
Casual, everyday word for 'secret'. Often used among friends or family. Can be used as '内緒にする' (keep it a secret) or '内緒だよ' (it's a secret).
Literally 'to be silent'. Implies keeping quiet about something, often used when you choose not to reveal information.
Please keep quiet about this.
Formal expression meaning 'not to disclose' or 'keep confidential'. Often used in business or official contexts.
Literary/poetic word meaning 'to keep hidden (in one's heart)'. Used for emotions or thoughts.
Specifically about guarding someone else's confidential information.
Hiding information from a particular person or group.
Casual pattern: 'keep it a secret from ~'. Replace 〜 with the person.
Emphasizing the act of not speaking about something.
The English phrase 'keep secret' cannot be directly translated word-for-word into Japanese. Expressions like '秘密を保つ' (keep a secret) are understandable but unnatural. Use the options above instead.
秘密 (himitsu) is the standard word for 'secret' and can be used in most situations. 内緒 (naisho) is more casual and intimate, often used among close friends or family. 内緒 implies a shared, often light-hearted secret, while 秘密 can be serious or formal.
これは内緒だよ。
This is a secret, okay?
Keep it a secret, okay?
He kept silent without saying anything.
Please do not disclose this information.
彼女は心に秘めた思いを誰にも話さなかった。
She never told anyone the feelings she kept hidden in her heart.
It's important to keep a friend's secret.
Formal, somewhat stiff expression meaning 'not to tell others'. Often used in promises.
I promise not to tell anyone about this.
Keep it a secret from Mom.
Neutral pattern: 'keep it a secret from ~'.
I'm keeping it a secret from him.
Literally 'shut one's mouth'. Stronger, more dramatic way to say 'keep silent'.
He kept his mouth shut about the matter.
Idiom meaning 'to impose a gag order'. Used in formal or organizational contexts.
The government imposed a gag order on the incident.