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secrecy; confidentiality; privacy; secret
one's circumstances (esp. fiscal)
inner realization; personal enlightenment
kitchen
彼は転職のことを家族にも内所にしていた。
He kept his job change a secret even from his family.
内所で貯めたお金を妻の誕生日に使うつもりだ。
I plan to spend my secretly saved money on my wife's birthday.
この話は二人だけの内所にしておいてほしい。
I want this to remain a secret between just the two of us.