cost·​ly ˈkȯs(t)-lē How to pronounce costly (audio)
costlier; costliest
: commanding a high price especially because of intrinsic worth
costly gems
: made or done at heavy expense or sacrifice
a costly mistake
costliness noun

Example Sentences

We use less costly materials in our products. It was too costly to fix her car after the accident, so she decided to buy a new car instead. They won the game, but their best player was injured, so it was a costly victory. The decision to wait could be a costly mistake.
Recent Examples on the Web Regulation and government control can discourage new development, make housing more costly, and have fewer rental units available. San Diego Union-Tribune, 20 Jan. 2023 Ukraine wants to make Russia's advances as costly as possible. Hanna Arhirova, ajc, 15 Jan. 2023 However, the paper notes that dredging is costly and usually only a temporary solution, while flushing can result in unexpected consequences as a deluge of soil and other materials flow downstream. Doug Johnson, Ars Technica, 12 Jan. 2023 But semiconductors capable of splitting water are far more expensive than standard silicon solar panels, making that option too costly. Byrobert F. Service,, 4 Jan. 2023 While the garage will still be made up of five floors, those floors will be smaller, and make maintenance of the garage less costly, Brennan said. cleveland, 24 Dec. 2022 Putin’s goal now seems intent on making such help so costly that Kyiv’s Western backers give up. David L. Stern, Washington Post, 15 Dec. 2022 Excellent credit can qualify you for a better interest rate and loan amount, but bad credit can make loans costly. Dallas News, 28 Nov. 2022 Although this is lower than the 14.1% rate in the U.S., high energy prices in Europe could make building costly for several years. Carol Ryan, WSJ, 22 Nov. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'costly.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

14th century, in the meaning defined at sense 1a

Time Traveler
The first known use of costly was in the 14th century

Dictionary Entries Near costly

Cite this Entry

“Costly.” Dictionary, Merriam-Webster, Accessed 27 Jan. 2023.

Kids Definition


cost·​ly ˈkȯs(t)-lē How to pronounce costly (audio)
costlier; costliest
: of great cost or value
costly furs
: gained at great expense or sacrifice
a costly victory
costliness noun

More from Merriam-Webster on costly

Last Updated: - Updated example sentences
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