costly
Americanadjective
-
costlier,
comparative
-
costliest
superlative
-
costing much; expensive; high in price.
a costly emerald bracelet; costly medical care.
- Synonyms:
- high-priced, dear
-
resulting in great expense.
The upkeep of such a large house is costly.
-
resulting in great detriment.
It was a costly mistake because no one ever trusted him again.
-
of great value; very valuable; sumptuous.
-
lavish; extravagant.
adjective
-
of great price or value; expensive
-
entailing great loss or sacrifice
a costly victory
-
splendid; lavish
Synonym Usage
See expensive.
Other Word Forms
Derived Forms
Inflected Forms
Adjectives
Etymology
Origin of costly
First recorded in 1350–1400, costly is from the Middle English word costli. See cost, -ly
Explanation
Something that's costly is expensive. The worst kind of news you can hear from your car mechanic is that you need costly repairs. Things that cost a lot of money are costly, but you can also use the word for events that cost you other things — like time, happiness, or advantage. A soldier's costly mistake might result in someone's death, and a costly law might end up hurting the people it's meant to help.In the 13th century, costful was used instead, and both words stem from cost, which has a Latin root, constare, "to stand at," or "to cost."
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
It also helped unleash an online backlash against the health-insurance industry, particularly authorization requirements that can block patients’ access to costly procedures and drugs.
From The Wall Street Journal ● Aug. 14, 2026
The heatwaves pummelling Europe this summer will have costly impacts on industries ranging from agriculture to tourism -- but that hasn't stopped stock markets from hitting all-time highs.
From Barron's ● Aug. 14, 2026
If there is a mortgage, lenders generally require insurance to remain active and may impose costly force-placed insurance if coverage lapses.
From MarketWatch ● Aug. 13, 2026
The Holston Army Ammunition Plant churns out explosives used in Patriot missiles, warheads and other heavy weaponry in the midst of the country's costly and prolonged war with Iran.
From BBC ● Aug. 12, 2026
The commercial potential for the stuff–which soon became known as phosphorus, from Greek and Latin roots meaning "light bearing"–was not lost on eager businesspeople, but the difficulties of manufacture made it too costly to exploit.
From "A Short History of Nearly Everything" by Bill Bryson
The diversions mark the latest redrawing of global oil flows after months of war have forced producers, traders and shipowners to abandon familiar routes for ever costlier detours.
From The Wall Street Journal ● Jul. 26, 2026
But their coverage tends to be skimpier and often costlier than policies sold by travel insurers.
From MarketWatch ● Jul. 9, 2026
Higher interest rates make it costlier to borrow money, which acts as a brake on spending, employment, and economic growth.
From Slate ● Jun. 17, 2026
While the $6 million in damages is small potatoes for two of the world’s largest corporations, the March verdict could presage much costlier lawsuits.
From Barron's ● Jun. 15, 2026
But they bowed to Sproul’s judgment that losing Lawrence would be even costlier, and voted to cover all the annual operating and maintenance costs that Lawrence had budgeted for the Rad Lab.
From "Big Science" by Michael Hiltzik
It’s a difficult calculation for teams, especially because the last couple of years have shown that the costliest financial mistake in all of football is handing out one of those megadeals to the wrong quarterback.
From The Wall Street Journal ● Aug. 10, 2026
It was reported to be the costliest documentary film of all time, even with production costs undisclosed.
From MarketWatch ● Apr. 30, 2026
Later in the year, Jaguar Land Rover was attacked, in what became the costliest cyber event in UK history.
From BBC ● Apr. 1, 2026
"It's very expensive to run a war," he said, noting that on a day-to-day basis, the Iran conflict "has to be up there with the costliest interventions the US has undertaken from a financial perspective."
From Barron's ● Mar. 19, 2026
When Cortes and his Indian allies finally attacked, the Mexica resisted so fiercely despite their weakness that the siege has often been described as the costliest battle in history—casualty estimates range up to 100,000.
From "1491" by Charles C. Mann
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.
