exhaust

American  

[ig-zawst] / ɪgˈzɔst /

verb (used with object)

1. to drain of strength or energy, wear out, or fatigue greatly, as a person.

   I have exhausted myself working.

   Synonyms:

   debilitate, prostrate, enervate, tire

   Antonyms:

   invigorate, strengthen

2. to use up or consume completely; expend the whole of.

   He exhausted a fortune in stock-market speculation.

   Synonyms:

   dissipate, squander, waste

3. to draw out all that is essential in (a subject, topic, etc.); treat or study thoroughly.

4. to empty by drawing out the contents.

   to exhaust a tank of fuel oil.

   Synonyms:

   void

   Antonyms:

   fill

5. to create a vacuum in.

6. to draw out or drain off completely.

7. to deprive wholly of useful or essential properties, possessions, resources, etc.

8. Chemistry, Pharmacology. to deprive of ingredients by the use of solvents, as a drug.

9. to destroy the fertility of (soil), as by intensive cultivation.

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verb (used without object)

1. to pass out or escape, as spent steam from the cylinder of an engine.

noun

Machinery.

1. the escape of steam or gases from the cylinder of an engine.

2. the steam or gases ejected.

   Synonyms:

   vapor, smoke, fume

3. Also called exhaust system.  the parts of an engine through which the exhaust is ejected.

exhaust British  

/ ɪɡˈzɔːst /

verb

1. to drain the energy of; tire out

   to exhaust someone by constant questioning

2. to deprive of resources, etc

   a nation exhausted by war

3. to deplete totally; expend; consume

   to exhaust food supplies

4. to empty (a container) by drawing off or pumping out (the contents)

5. to develop or discuss thoroughly so that no further interest remains

   to exhaust a topic of conversation

6. to remove gas from (a vessel, etc) in order to reduce the pressure or create a vacuum; evacuate

7. to remove or use up the active ingredients from (a drug, solution, etc)

8. to destroy the fertility of (soil) by excessive cultivation

9. (intr) (of steam or other gases) to be emitted or to escape from an engine after being expanded

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noun

1. gases ejected from an engine as waste products

2. 1. the expulsion of expanded gas or steam from an engine

   2. ( as modifier )

      exhaust stroke

3. 1. the parts of an engine through which the exhausted gases or steam pass

   2. ( as modifier )

      exhaust valve

      exhaust pipe

Other Word Forms

• exhausted
  adjective
• exhauster
  noun
• exhaustibility
  noun
• exhaustible
  adjective
• exhausting
  adjective
• multiexhaust
  noun
• nonexhausted
  adjective
• nonexhaustible
  adjective
• preexhaust
  verb (used with object)
• unexhausted
  adjective
• unexhaustedly
  adverb

Etymology

Origin of exhaust

1515–25; 1895–1900 exhaust for def. 11; < Latin exhaustus emptied out, drained out, past participle of exhaurīre

Explanation

The noun exhaust refers to what comes out of your car's tailpipe. It consists of the burned gases and particulate matter that are created by the engine. As a verb, the word exhaust means to use something up, such as a food supply or your energy. The exhaust system in your car is the part that takes the waste created by the car in the form of gas or smoke and expels it through the tailpipe. The noun exhaust appeared in the 19th century, after the invention of the engine. Before that, the word, as a verb, referred only to depleting something, such as a natural resource. Miners deplete a mineral deposit and exhaust the resource.

Example Sentences

Jet exhaust is a major contributor to climate change, 3% to 4% of all warming, and air travel is usually the biggest contributor to carbon emissions from major sporting events.

From Los Angeles Times • May 18, 2026

Because methylsiloxanes are highly heat resistant and do not fully break down during combustion, some survive the intense temperatures inside engines and are released into the atmosphere through exhaust gases.

From Science Daily • May 13, 2026

Sport mode will awaken a growl in the exhaust pipes but that’s not what pays the SL 680’s bills.

From The Wall Street Journal • May 2, 2026

The volunteers, he says, "really get their teeth into these old cases" and "exhaust every avenue".

From BBC • Apr. 29, 2026

Unfortunately, it turned out to be too thick for tying his exhaust pipes in place.

From "Ralph S. Mouse" by Beverly Cleary

Related Words

• drain
• fatigue
• frazzle
• impoverish
• overwork
• sap
• tire out
• use up
• weaken
• wear out
• weary