depreciate

v. reduce the value or cost (of an item or a currency); be reduced in value or cost; disparage

Depreciation is a term used in accounting, economics and finance with reference to the fact that assets with finite lives lose value over time. (There is also a separate use in international finance to refer to a reduction in the exchange rate of a currency - see Depreciation (currency)). In accounting, depreciation is a term used to describe any method of attributing the historical or purchase cost of an asset across its useful life, roughly corresponding to normal wear and tear. It is of most use when dealing with assets of a short, fixed service life, and which lose value over that life.
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Verb
1. belittle; "The teacher should not deprecate his student's efforts"
(synonym) deprecate
(hypernym) disparage, belittle, pick at
(hyponym) deflate, puncture
(derivation) disparagement, depreciation, derogation
2. lower the value of something; "The Fed depreciated the dollar once again"
(antonym) appreciate, apprize, apprise
(hypernym) devalue
(hyponym) write off, write down
(verb-group) undervalue, devaluate, devalue
(derivation) depreciation, wear and tear
3. lose in value; "The dollar depreciated again"
(synonym) undervalue, devaluate, devalue
(antonym) appreciate, apprize, apprise, revalue
(hypernym) decrease, diminish, lessen, fall
(derivation) depreciation, wear and tear

v. depreciate

(v. t.)
To lessen in price or estimated value; to lower the worth of; to represent as of little value or claim to esteem; to undervalue.
  

(v. i.)
To fall in value; to become of less worth; to sink in estimation; as, a paper currency will depreciate, unless it is convertible into specie.