these four walls
成語所屬單字wall
these four walls — 慣用語
1. used to talk about keeping a secret within a small, private group, implying that
1.慣用語
釋義
絕不外傳；僅限於此
used to talk about keeping a secret within a small, private group, implying that the information must not be told to anyone outside that space.
例句
Please keep what I said within these four walls — do not tell anyone else.
What is discussed in this room stays within these four walls, understood?