smell a rat, to

smell a rat

To suspect an instance of betrayal, deception, or corruption. A: "Their numbers don't match up with the taxes they've paid." B: "Hmm, I smell a rat." She thought she smelled a rat when she saw John slinking away from the scene of the crime.
See also: rat, smell
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

smell a rat

to suspect that something is wrong; to sense that someone has caused something wrong. I don't think this was an accident. I smell a rat. Bob had something to do with this. The minute I came in, I smelled a rat. Sure enough, I had been robbed.
See also: rat, smell
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

smell a rat

Suspect something is wrong, especially a betrayal of some kind. For example, When I didn't hear any more from my prospective employer, I began to smell a rat. This expression alludes to a cat sniffing out a rat. [c. 1550]
See also: rat, smell
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

smell a rat

INFORMAL
COMMON If you smell a rat, you believe that something is wrong in a particular situation, especially that someone is trying to deceive you or harm you. Once Caldere discovers the money is missing, he's going to smell a rat, isn't he? If only I'd thought it through, I'd have smelt a rat straight away and never touched the proposal.
See also: rat, smell
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012

smell a rat

begin to suspect trickery or deception. informal
See also: rat, smell
Farlex Partner Idioms Dictionary © Farlex 2017

ˌsmell a ˈrat

(informal) think or suspect that something is wrong or that somebody is trying to deceive you: She says that the business is making a lot of money, but I smell a rat somewhere. The figures are too good to be true.
See also: rat, smell
Farlex Partner Idioms Dictionary © Farlex 2017

smell a rat

tv. to suspect that something is wrong. Keep everything normal. I don’t want her to smell a rat. She has never had a surprise party before.
See also: rat, smell
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

smell a rat

Slang
To suspect that something is wrong.
See also: rat, smell
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

smell a rat, to

To suspect that something is wrong. Presumably this term, which is very old indeed, alludes to a cat sniffing out a rat. John Skelton used it in The Image of Hypocrisy (ca. 1550): “Yf they smell a ratt, they grisely chide and chant.”
See also: smell
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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