秘密 vs 内緒 – Which Japanese Word for Secret Should I Use?

秘密ひみつ is the closest Japanese word for secret. 内緒ないしょ also means secret but is closer to something private that is keep between select individuals.  Though both of these words are very similar They don’t mean exactly the same thing. So, when you want to say secret in Japanese you need to first know which word fits the situation best.

Which Japanese Word for Secret Should I Use?

You will probably use 秘密 for most situations as it has a broader range of usage than 内緒.

https://japaneseuniverse.com/2024/02/18/pac-man-in-japaneseconcepts-behind-development-to-global-icon/

内緒

So, both these words refer to something that you may want to hide from someone else but 内緒 is more informal and sounds less serious. It is usually used when you want to talk about something that a few people are keeping between each-other. Most of the time it is something small that does not have dramatic, far-reaching consequences.

この話はなしはお父とうさんに内緒ね
This is a secret to dad. (let’s keep this between us, and not tell dad)

The example above could be something that a mother and child or siblings are keeping to themselves.

秘密

If you are talking about 秘密 though, you can use this to talk about more serious secrets.

会社かいしゃの秘密がばれた
The companies secrets were found out

The last sentence would be weird to switch 秘密 for 内緒. You can also use 秘密 in a more general sense to talk about mysterious things, or things that not much people know of.

宇宙うちゅうの秘密
secrets of the universe

成功せいこうの秘密
secrets to success

Resource

• 秘密
• 内緒