Definition of costly
- a costly mistake
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.
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.
: having a high price : costing a lot
: causing people to lose something or to suffer
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