Exhaust may refer to:

In mathematics:

• Proof by exhaustion, proof by examining all individual cases
• Exhaustion by compact sets, in analysis, a sequence of compact sets that converges on a given set
• Collectively exhaustive, in probability and set theory, a collection of sets whose union equals the complete space
• Method of exhaustion, in geometry, finding the area of a shape by approximating it with polygons

In engines and technology:

• Exhaust gas, a gas which occurs as a result of combustion of fuel
• Exhaust system, a mechanism for venting exhaust gases from an internal combustion engine
• Exhaust velocity, a measure of engine efficiency
• Exhaust brake, a method of slowing diesel engines
• Exhaust manifold, a structure collecting an engine's exhaust outlets

In health:

• Heat exhaustion or Hyperthermia, a medical condition where the body is unable to control its accumulation of heat
• Nervous exhaustion or Neurasthenia, a nineteenth-century diagnosis encompassing fatigue, anxiety, and depression
• Adrenal exhaustion or Hypoadrenia, a hypothesized maladaption of the adrenal glands

In law:

• Exhaustion of remedies, restrictions on opening a suit in a new court while the original suit is still continuing
• Exhaustion of rights, the loss of intellectual property rights

In other uses:

• Exhaust (band), a clarinet, drum, and tape trio in Montreal, Canada
• Exhaustive ballot, a multi-round voting system
• Exhaust date, the projected date that a telecommunications area code will have assigned all of its numbers