Definition of propellant in English:

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Pronunciation: /prəˈpɛl(ə)nt/


1A substance that propels something, in particular:
Example sentences
  • Liquid helium from a tank in the lunar module was used to assure a steady flow of propellants to the descent engine.
  • Instead, the focus was to be on loads featuring some of the newer propellants.
  • Such a maneuver would require a significant amount of propellant for conventional rocket systems.
1.1An inert fluid, liquefied under pressure, in which the active contents of an aerosol are dispersed: the main uses of CFCs are in aerosols as propellants [mass noun]: aerosols are wastefully packaged, because they contain a lot of propellant as well as the product
More example sentences
  • They have uses as propellants in aerosol spray cans, refrigerant gases, and foaming agents for blown plastics.
  • These substances, also known as freons, were once used extensively as coolant fluids in refrigerators and air conditioners, and as propellants in aerosol cans.
  • Today, almost all aerosol cans contain alternative propellants, such as liquefied petroleum gas, which do not pose as serious a threat to the environment.
1.2An explosive that fires bullets from a firearm: the common gun propellants are either nitrocellulose or a mixture of nitrocellulose and nitroglycerine [mass noun]: the company produced all sizes of propellant for weapons
More example sentences
  • However, the use of this explosive mixture of saltpetre, charcoal, and sulphur as a propellant for bullets from firearms, and thus gun powder, is a western development and one which took place gradually from the 13th century.
  • Many of the wars in this century were fought with TNT as the main explosive and with gunpowder as the main propellant of bullets and artillery shells.
  • To fire the weapon a projectile containing the propellant and explosive is dropped into the muzzle.
1.3A substance used as a reagent in a rocket engine to provide thrust: rocket propellants
More example sentences
  • More like rocket engines, jets produce thrust by burning propellant (jet fuel mixed with air) and forcing the rapidly expanding gases rearward.
  • The extra propellant provides an additional 50 tonnes of thrust in the first 20 seconds following liftoff.
  • Perchlorate is a waterborne contaminant left over from propellants and rocket fuels.


Capable of propelling something: propellant gases
More example sentences
  • The cases are cleaned, inspected and reassembled for propellant casting, and a new nozzle and igniter are installed.
  • The missile consists of a two-stage solid propellant rocket motor, a separation system and three high density darts.
  • The mishap took place in the Center's solid propellant space booster plant, where rocket motors are filled with the solid fuel required for their operation.


Mid 17th century: originally from Latin propellent- 'driving ahead (of oneself)', from the verb propellere, later from propel.

Words that rhyme with propellant

appellant, propellent, repellent, water-repellent

For editors and proofreaders

Line breaks: pro¦pel|lant

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