C1adjective2K

Costly

UK /["/ˈkɒstli/"]/US /["/ˈkɔːstli/"]/

Definition

costing a lot of money, especially more than you want to pay

In simple words: Expensive; needing a lot of money.

Examples

  • Buying new furniture may prove too costly.
  • These measures could be costly to employers.
  • These teaching methods are too costly in terms of staff resources.
  • This process is costly in computer time.
  • The old palace may prove too costly for the Duke to maintain.
  • You want to avoid costly legal proceedings if you can.
  • a **costly mistake/failure**
  • Mining can be costly in terms of lives *(= too many people can die)*.
  • Privatizing the rail network turned out be a costly mistake for the government.
  • The six-month delay will be costly for the company.

Usage notes

Use 'costly' to describe something that requires a lot of money, especially in a neutral or formal context. Avoid using it in very casual settings, where simpler words like 'expensive' might be preferred.

Grammar pattern

costly + object

Memory hint

Sounds like 'cost'-'ly' — think of money costing you dearly.

Collocations

  • be
  • become
  • prove
  • extremely
  • fairly
  • very
  • for
  • in
  • in terms of
  • be
  • become
  • prove
  • extremely
  • fairly
  • very
  • for
  • in
  • in terms of

Synonyms

  • expensive
  • expensive

Antonyms

  • inexpensive
  • cheap

Common mistakes

  • Confused with 'cost' which refers to the price itself.
  • Used in a context where 'valuable' would be more appropriate.
  • Assuming it only refers to money when it can also refer to high costs in other aspects, like time.