costly
KOST-lee
Costly (adj) means Expensive, or requiring a heavy price to be paid. Example: “Leaving the lights on all day can be surprisingly costly.”
adj
1
Expensive, or requiring a heavy price to be paid.
"Leaving the lights on all day can be surprisingly costly."
"Repairing the roof turned out to be a costly job."
"It was a costly mistake that nearly ended the company."
How to use costly
Learner’s notesIn plain EnglishExpensive in money, or damaging in some other serious way, like a "costly error."
Common pairings
costly mistake
a costly delay
costly repairs
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Word forms
- Comparative
- costlier, more costly
- Superlative
- costliest, most costly
Fill the gap
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Leaving the lights on all day can be surprisingly _____.
Etymology
From Middle English costly, formed from cost plus -ly.
Synonyms
View more →Antonyms
costlessly
Related words
Rhymes for costly
See all rhymes for costly →Frequently asked questions
What does “costly” mean?
The word “costly” means expensive, or requiring a heavy price to be paid. In plain terms, expensive in money, or damaging in some other serious way, like a "costly error.".
How do you pronounce “costly”?
“Costly” is pronounced KOST-lee (/ˈkɒst.li/ in IPA).
How do you use “costly” in a sentence?
Here is “costly” used in a sentence: “Repairing the roof turned out to be a costly job.”
What is the opposite of “costly”?
The opposite of “costly” — its antonyms — is costlessly.
What part of speech is “costly”?
“Costly” is an adjective.
Where does the word “costly” come from?
The word “costly” comes from Middle English. From Middle English costly, formed from cost plus -ly.
Is “costly” a common word?
“Costly” is a fairly common word in modern English, usually learned at around the B2 level.
What is the difference between costly and expensive?
Both mean requiring a lot of money and often overlap. However, "costly" frequently implies a heavy price beyond money — such as damage or loss, as in "a costly mistake" — while "expensive" refers more directly to a high monetary price.
What is the difference between costly and pricey?
Costly and pricey both describe something that costs a lot, but pricey is more informal and casual. Costly is more formal and can also suggest serious consequences, not just a high price tag.
Can 'costly' describe something that does not involve money?
Yes. Besides meaning expensive, costly can describe anything that requires a heavy price to be paid, such as a costly error in judgement or a costly victory won at great loss.
What is the difference between costly and valuable?
Costly means something has a high price or requires a heavy cost to obtain. Valuable means something is worth a great deal, whether in money, usefulness, or importance. A costly item is not always valuable, and a valuable item is not always costly.
