# exhaust

Pronunciation: say "ig-ZAWST" US /ɪɡˈzɔst/, UK /ɪɡˈzɔːst/

## Verb

1. To use something up completely, so that the supply or stock of it comes to an end.
   - Simple: To use all of something until there is none left.
   - _Planners warn that the city could exhaust its water reserves within a decade._
   - _By midnight the search team had exhausted every possible lead._
2. To tire someone out completely, wearing them down until they have no energy left.
   - Simple: To make someone so tired that they have no energy left.
   - _Back-to-back night shifts exhaust even the youngest nurses on the ward._
   - _The steep climb exhausted the hikers, so they rested for an hour at the ridge._
6. To draw off or let out the whole of something, such as water or moisture, draining it away completely.
   - Simple: To take or let out all of something, like water, until it is drained.
   - _Engineers needed two large pumps to exhaust the floodwater from the mine._
   - _Hot, dry winds exhaust the moisture from the topsoil within days._
7. To empty a container or space by drawing off or letting out its contents.
   - Simple: To empty something by taking out or letting out everything inside it.
   - _Technicians exhaust the test chamber of air before each run begins._
   - _The divers waited while the ballast tank was exhausted and refilled with seawater._
8. To discuss a topic thoroughly and completely, leaving nothing more to be said about it.
   - Simple: To talk about a subject so fully that there is nothing left to say.
   - _By the third hour the committee had exhausted the topic and turned to the budget._
   - _Few historians manage to exhaust a subject as large as the Civil War in a single book._
9. To expel used air or gas from a space or machine as exhaust.
   - Simple: To push used air or gas out of a place or machine.
   - _Many hospital wards exhaust stale air outdoors instead of recirculating it._
   - _The factory exhausts its fumes through a tall stack behind the plant._
10. To discharge spent gas or steam, or to escape as exhaust, typically through a pipe, port or vent.
   - Simple: To flow out as used gas or steam, often through a pipe.
   - _Both cylinders exhaust into a shared pipe that leads up to the stack._
   - _When the valve shifts, the line exhausts through the side port and the pressure drops._
13. To treat a material with various solvents in order to remove all of its soluble substances or extractives.
   - Simple: To soak a substance in different liquids until everything in it that can dissolve is taken out.
   - _To recover the active compounds, chemists exhaust the ground bark first with water and then with ether._
   - _Once the root had been exhausted with three solvents, the remaining fiber was dried and weighed._

## Noun

3. Waste gas given off by an engine as it burns fuel.
   - Simple: The gas that comes out of an engine after it burns fuel.
   - _Diesel exhaust hung over the loading dock all morning._
   - _During rush hour, idling trucks fill the downtown streets with exhaust._
4. The set of engine parts through which burned gases or steam are carried away and released.
   - Simple: The parts of an engine that carry the used gas or steam away and let it out.
   - _A leak anywhere in the exhaust can let fumes seep into the cabin._
   - _The locomotive's exhaust was rebuilt to carry spent steam away from the cylinders more freely._
5. The pipe through which waste gases leave an engine, especially on a motor vehicle.
   - Simple: The pipe that lets used gas out of an engine, mostly on cars and trucks.
   - _His motorcycle has a chrome exhaust that sweeps up past the rear wheel._
   - _A loose exhaust was dragging along the road behind the pickup, throwing sparks._
11. Air containing impurities that a ventilation outlet or pipe carries out of a room.
   - Simple: The dirty air that is let out of a room through a vent or pipe.
   - _Exhaust from the operating rooms is filtered before it leaves the building._
   - _The stale exhaust from the crowded classroom escaped through a grille near the ceiling._
12. Spent steam let out of an engine's cylinder once it has done its work there.
   - Simple: Used steam that comes out of a steam engine after it has done its work.
   - _The locomotive's sharp exhaust echoed off the canyon walls as it climbed the grade._
   - _On cold mornings the exhaust from the old engine hung over the station in white clouds._

## Adjective

14. Used up completely, so that none is left. *(obsolete)*
   - Simple: Used up, with nothing left.

## Origin

From Latin exhaustus, the past participle of exhaurīre ("to draw out, drink up, empty, exhaust"), formed from ex ("out") + haurīre ("to draw, especially water; to drain").

Source: DictionaryAI, https://dictionaryai.com/define/exhaust (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).