I'm preparing a sales presentation; it contains some company data and I want to indicate that the entire presentation is confidential. In English, this would likely be accomplished by stamping the corner with "confidential".
What's the best word to use in Japanese for a similar meaning? I've seen this somewhere in my old company, but I forgot... here are the candidates I know of, but the one I think I've seen before isn't there, I'm having trouble finding something where I say "aha that's it".
- 内緒 (ないしょ) -- more used as in "private", like a small secret between a few people
- 秘密 (ひみつ -- "secret", but not sure if this is the appropriate word
- 機密 (きみつ）-- don't understand how this is different than 秘密
- 親展 (しんてん) -- you see this on envelopes of letters, but that's about it