- costing much; expensive; high in price: a costly emerald bracelet; costly medical care.
- 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.
Origin of costly
SynonymsSee more synonyms on Thesaurus.com
1. dear, high-priced. See expensive.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for costliest
Child care is probably the costliest part of having a severely disabled child.The Cost of Raising a Special Needs Son
June 11, 2014
If estimates come in at the higher end of the range, it could be the costliest since Hurricane Katrina.As Much of New York and New Jersey Remain Paralyzed and Devastated, the Costs From Sandy Continue to Climb
November 2, 2012
The race features two mega-millionaires, in a contest that promises to be one of the costliest in American history.A Candidate Shuns His Family Fortune
Samuel P. Jacobs
September 30, 2010
But our employer-based system already delivers the costliest health care on the planet.Will Business Kill Health Care?
June 15, 2009
War is infinitely more costly than the costliest preparedness.Camps, Quarters and Casual Places
She was the richest of all the girls and wore the costliest clothes.Grace Harlowe's Plebe Year at High School
Jessie Graham Flower
On the contrary, they have bought and enjoyed the costliest things.The Common Sense of Socialism
Her last and costliest purchase she would have been better without.Our Little Lady
Emily Sarah Holt
It is the stateliest and the costliest ever erected to the memory of any man.The Letters Of Mark Twain, Volume 2, 1867-1875
Mark Twain (Samuel Clemens)
- of great price or value; expensive
- entailing great loss or sacrificea costly victory
- 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
Word Origin and History for costliest
Online Etymology Dictionary, © 2010 Douglas Harper