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Synonyms

costly

American  
[kawst-lee, kost-] / ˈkɔst li, ˈkɒst- /

adjective

costlier, costliest

  1. costing much; expensive; high in price.

    a costly emerald bracelet; costly medical care.
    Synonyms:
    high-priced, dear

  2. resulting in great expense.

    The upkeep of such a large house is costly.

  3. resulting in great detriment.

    It was a costly mistake because no one ever trusted him again.

  4. of great value; very valuable; sumptuous.

  5. lavish; extravagant.

costly British  
/ ˈkɒstlɪ /

adjective

  1. of great price or value; expensive

  2. entailing great loss or sacrifice

    a costly victory

  3. splendid; lavish

"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

Related Words

See expensive.

Other Word Forms

  • costliness noun
  • overcostliness noun
  • overcostly adjective
  • uncostly adjective

Etymology

Origin of costly

First recorded in 1350–1400, costly is from the Middle English word costli. See cost, -ly

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.