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hi-fi

American  
[hahy-fahy] / ˈhaɪˈfaɪ /

noun

  1. high fidelity.

  2. a phonograph, radio, or other sound-reproducing apparatus possessing high fidelity.

adjective

  1. of, relating to, or characteristic of such apparatus; high-fidelity.

hi-fi British  
/ ˈhaɪˈfaɪ /

noun

    1. short for high fidelity

    2. ( as modifier )

      hi-fi equipment

  2. a set of high-quality sound-reproducing equipment

"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

Etymology

Origin of hi-fi

1945–50, shortened form of high fidelity

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.