(someone had) better keep still about it
(Someone had) better not say anything about a particular issue or situation. "Someone" can be used in the phrase itself, especially when the listener already knows who the speaker is talking about. A: "I think Jake knows that we doctored the numbers in that report." B: "Well, someone had better keep still about it then." Better keep still about it so that the boss doesn't suspect anything. If she knows that the damning claims are true, then she better keep still about it—they could destroy the whole company.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.
Better keep still about it.
and Someone had better keep still about it.; Better keep quiet about it.; Someone better keep quiet about it.A particular person ought not to tell about or discuss something. (The someone can stand for any person's name, any pronoun, or even the word someone meaning "you-know-who." If there is no Someone had, the phrase is a mild admonition to keep quiet about something.) Mary: I saw you with Bill last night. Jane: You'd better keep quiet about it. Jane: Tom found out what you're giving Sally for her birthday. Bill: He had better keep quiet about it!
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.