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Synonyms

cold fish

American  

noun

Informal.
  1. a person who is very reserved or aloof in manner or who lacks normal cordiality, sympathy, or other feeling.


cold fish British  

noun

  1. an unemotional and unfriendly person

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

cold fish Idioms  
  1. A hard-hearted, unfeeling individual, one who shows no emotion, as in Not even the eulogy moved him; he's a real cold fish. This expression was used by Shakespeare in The Winter's Tale (4:4): “It was thought she was a woman, and was turn'd into a cold fish.” However, it came into wider use only in the first half of the 1900s.


Etymology

Origin of cold fish

First recorded in 1940–45