pour/throw cold water on something

pour cold water on (something)

To discourage or deter someone from doing something; to make something seem less appealing or reduce someone's enthusiasm for something. News of unrest in the area really poured cold water on our plans to vacation there. Slashing your employees' benefits is a great way to throw cold water on their plans to stick with your company.
See also: cold, on, pour, water
Farlex Dictionary of Idioms.

pour cold water on something

 
1. Lit. to douse something with cold water. Pour cold water on the vegetables to freshen them. I poured cold water on my head to cool myself off.
2. and dash cold water on something; throw cold water on something Fig. to discourage doing something; to reduce enthusiasm for something. (Alludes to cooling passion with cold water.) When my father said I couldn't have the car, he poured cold water on my plans. John threw cold water on the whole project by refusing to participate.
See also: cold, on, pour, water
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

pour cold water on

Also, throw cold water on. Discourage or deter, as in Cutting my year-end bonus poured cold water on my loyalty to the company, or Hearing about the outbreak of cholera threw cold water on our plans to visit Bolivia. This term, with its image of putting out a fire with water, at one time meant "defame" or "slander"; the modern meaning dates from about 1800.
See also: cold, on, pour, water
The American Heritage® Dictionary of Idioms by Christine Ammer.

pour cold water on something

or

throw cold water on something

COMMON If someone pours cold water on someone else's idea or plan or throws cold water on it, they criticize it and express no enthusiasm for it. Rachel found it frustrating when he poured cold water on one of her ideas. Mr Powell said that neither France nor Germany had thrown cold water on his proposal.
See also: cold, on, pour, something, water
Collins COBUILD Idioms Dictionary, 3rd ed.

pour (or throw) cold water on

be discouraging or negative about a plan or suggestion.
1998 New Scientist When I put it to…the health minister, that perhaps all clinical trial results should be published, she threw cold water on the idea.
See also: cold, on, pour, water
Farlex Partner Idioms Dictionary

pour/throw cold ˈwater on something

(informal) discourage or try to prevent a plan, etc. from being carried out; be unenthusiastic about something: I’ve had lots of ideas about how to improve sales but my manager pours cold water on all my suggestions.
See also: cold, on, pour, something, throw, water
Farlex Partner Idioms Dictionary

pour cold water on something

tv. to put an end to something; to dampen something. I wanted to go to the party, but my brother poured cold water on that by taking the car.
See also: cold, on, pour, something, water
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions

throw cold water on

To express misgivings about or disapproval of; discourage.
See also: cold, on, throw, water
American Heritage® Dictionary of the English Language, Fifth Edition.
See also:
  • (someone or something) promises well
  • accompanied by
  • accompanied by (someone or something)
  • accompany
  • a fast talker
  • a slue of (something)
  • (have) got something going (with someone)
  • a ghost at the feast
  • a/the feel of (something)
  • (I) wouldn't (do something) if I were you