exhaust

exhaust — noun

1. the waste gas produced by an engine in a car, truck, or other vehicle, or the pi

1.nounB1
Definition

the waste gas produced by an engine in a car, truck, or other vehicle, or the pipe or system through which this gas flows out of the vehicle.

Example

The mechanic said the exhaust was rusted and needed a new pipe.

countable: refers to the pipe/system

Diesel exhaust contains tiny particles that can damage people's lungs over time.

uncountable: refers to the gas

Common collocations
  • exhaust fumes
  • exhaust pipe
  • exhaust system
  • diesel exhaust
  • car exhaust
Synonyms
  • emissions

    broader; refers to any substance released, not just engine waste gas

  • fumes

    informal focus on the smelly/harmful gas aspect, not the pipe

Grammar Patterns

the exhaust

exhaust + noun

Usage Note

As an uncountable noun, exhaust means the gas itself ('exhaust fumes'). As a countable noun, it usually refers to the pipe or system ('a new exhaust'). The plural form 'exhausts' is rare in everyday English.

Common Mistakes

The car's exhaust pipe was leaking exhaust gas from the exhaust.
The car's exhaust system was leaking fumes.
'exhaust' alone can refer to the pipe or the gas, so be clear which you mean.

exhaust — verb

Word family

Synonym discussion

Sense: verb/2

Exhaust means using something completely until nothing is left — it carries the strongest sense of emptiness ('the money was exhausted'). Deplete is more formal and often describes gradual reduction of natural resources ('overfishing depleted the ocean's fish stocks'). Use up is the everyday phrasal verb: it is the most natural choice in casual conversation ('the kids used up all the hot water'). Consume is broader and can mean using part or all of something; it does not guarantee emptiness ('the factory consumes a lot of electricity'). Drain suggests something flowing away gradually, often used metaphorically ('the long legal battle drained their savings'). For learners: when you want to say all of something is gone, choose exhaust or use up; for partial use, choose consume.

exhaust ↗depleteuse up ↗consume ↗drain ↗

Common collocations

Nouns

Adverbs

Phrases

  • exhaust emissions
  • exhaust system
  • exhaust pipe
  • exhaust all possibilities

Prepositions

Etymology

LatinFrenchEnglish

Exhaust entered English in the mid-1500s from Latin exhaustus, the past participle of exhaurire, meaning 'to draw out, drain out, empty'. The prefix ex- means 'out', and haurire means 'to draw or drain'. The original sense was about physically emptying a container of liquid. By the 1600s it had developed the broader meaning of using up any resource completely. The noun sense for engine waste gas appeared in the late 1800s, soon after the invention of the internal combustion engine.