How to say keep a secret in Japanese

How to say keep a secret in Japanese

How do you say “Secret” in Japanese?

In general, 秘密 (ひみつ / himitsu) is the commonly used word.

Example usage would be:

秘密の扉
ひみつのとびら
himitsu no tobira
secret door

家族の秘密
かぞくのひみつ
kazoku no himitsu
family secret

成功の秘密
せいこうのひみつ
seikou no himitsu
secret(s) to success

The word 秘密 has a bigger, generalized/longer lasting feel to it.

If you are talking about a personal secret, then 内緒 (ないしょ / naisho) , meaning “for your eyes only” or “[in] confidence/secret” is often used.

Example:
これは内緒だよ。
これはないしょだよ。
kore wa naisho dayo
please keep this a secret.

内緒の話
ないしょのはなし
naisho no hanashi
secret conversation

内緒でたばこを吸う）
ないしょでたばこをすう
naisho de tabako wo suu
smoke in secret

The word 内緒 has less formal/a little more personal/temporary feel to it.

If it’s an institutional secret, e.g. a government or military secret, then 機密（きみつ/ kimitsu) is used.

機密文書 （きみつぶんしょ）
kimitsu bunsho
confidential /classified document

So if I were asking someone to keep something a secret for time being in a friend-to-friend conversation, I’d say:

これは内緒にしておいて。
kore wa naisho ni shite oite
please keep this a secret for now.

vs. If I were in an office, and talking about something I want to keep under wraps:

“これは今（いま）のところ秘密ですが、佐藤（さとう）さんは転勤（てんきん）するそうです。”
Kore wa ima no tokoro himitsu desuga, Sato-san wa tenkin suru soudesu.
(This is a secret for now, but Mr./Ms. Sato will be transferred to another office.)

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