cost

UK: /ˈkɒst/ US: /kɔst, kɑst/ ,(kôst, kost)

Inflections of 'cost' (v): (⇒ conjugate)

costs

v 3rd person singular

costing

v pres p

costed

v past (Senses relating to estimating or determining cost only)

cost

v past (All other usages)

costed

v past p (Senses relating to estimating or determining cost only)

cost

v past p (All other usages)

WordReference Random House Learner's Dictionary of American English © 2025

cost /kɔst, kɑst/   n., v., cost or, for 11-13. cost•ed, cost•ing. 
n. 

1. the price paid to buy, produce, or maintain anything:
   [countable* usually singular] The cost of a new home in that area is about $500,000.
2. an outlay or expenditure of money, time, etc.:
   [countable] Production costs are too high.
3. a sacrifice or penalty to endure:
   [countable* usually singular] The battle was won, but at a heavy cost in casualties.
4. the price that the seller of merchandise paid to buy it:
   [uncountable] We are selling these chairs at cost, so hurry in today.
5. Law costs, [plural] money awarded to a person who wins a court action, to pay for legal expenses.

v. 

6. to require the payment of (money) in an exchange;
   have (a sum of money) as the price of: [~ + object]
   [not: be + ~-ing] That camera costs $200.
   [~ + object + object]
   That camera cost us $200.
7. to result in the loss or injury of: [~ + object]
   Carelessness costs lives.
   [~ + object + object]
   Drugs can cost you your life.
8. [~ + object + object] to cause to pay:
   Worrying cost me many sleepless nights.
9. to estimate the cost of (manufactured articles, etc.):
   [~ + object] We spent weeks trying to cost the new computer lab.

Idioms

10. Idioms at all costs, by any means necessary:
    You've got to keep that programmer working for us at all costs.

Related Words

cost is a noun and a verb, costly is an adjective:
The costs are high. How much does it cost? Those are costly diamonds.

WordReference Random House Unabridged Dictionary of American English © 2025

cost  (kôst, kost), n., v., cost or, for 11–13, cost•ed, cost•ing. 
n. 

1. the price paid to acquire, produce, accomplish, or maintain anything:
   the high cost of a good meal.
2. an outlay or expenditure of money, time, labor, trouble, etc.:
   What will the cost be to me?
3. a sacrifice, loss, or penalty:
   to work at the cost of one's health.
4. Law costs:
   • money allowed to a successful party in a lawsuit in compensation for legal expenses incurred, chargeable to the unsuccessful party.
   • money due to a court or one of its officers for services in a cause.
5. Idioms at all costs, regardless of the effort involved;
   by any means necessary:
   The stolen painting must be recovered at all costs.
   Also, at any cost. 

v.t. 

6. to require the payment of (money or something else of value) in an exchange:
   That camera cost $200.
7. to result in or entail the loss of:
   Carelessness costs lives.
8. to cause to lose or suffer:
   The accident cost her a broken leg.
9. to entail (effort or inconvenience):
   Courtesy costs little.
10. to cause to pay or sacrifice:
    That request will cost us two weeks' extra work.
11. to estimate or determine the cost of (manufactured articles, new processes, etc.).

v.i. 

12. to estimate or determine costs, as of manufacturing something.
13. cost out, to calculate the cost of (a project, product, etc.) in advance:
    to cost out a major construction project.

• Anglo-French, Old French, noun, nominal derivative of the verb, verbal
• Latin constāre to stand together, be settled, cost; compare constant; (noun, nominal) Middle English
• Anglo-French, Old French co(u)ster
• (verb, verbal) Middle English costen 1200–50

cost′less, adj. 
cost′less•ness, n. 
Synonyms

• 1. charge, expense, expenditure, outlay. See price. 
• 3. detriment.

cost-, 

1. var. of costo- before a vowel:
   costate.

Collins Concise English Dictionary © HarperCollins Publishers::

cost / kɒst/ noun

1. the price paid or required for acquiring, producing, or maintaining something, usually measured in money, time, or energy; expense or expenditure; outlay
2. suffering or sacrifice; loss; penalty: count the cost to your health, I know to my cost
3. the amount paid for a commodity by its seller: to sell at cost
4. (as modifier): the cost price
5. (plural) the expenses of judicial proceedings
6. at any cost, at all costs ⇒ regardless of cost or sacrifice involved
7. at the cost of ⇒ at the expense of losing

verb (costs, costing, cost)

1. (transitive) to be obtained or obtainable in exchange for (money or something equivalent); be priced at: the ride cost three pounds
2. to cause or require the expenditure, loss, or sacrifice (of): the accident cost him dearly
3. to estimate the cost of (a product, process, etc) for the purposes of pricing, budgeting, control, etc

Etymology: 13th Century: from Old French (n), from coster to cost, from Latin constāre to stand at, cost, from stāre to stand

WordReference Random House Unabridged Dictionary of American English © 2025

costo-, 

1. a combining form meaning "rib,'' used in the formation of compound words:
   costoclavicular.

Also,[esp. before a vowel,] cost-. 

• Latin cost(a) rib (see costa) + -o-