propellant

1 of 2

adjective

pro·​pel·​lant prə-ˈpe-lənt 

variants or less commonly propellent

: capable of propelling

propellant

2 of 2

noun

variants or less commonly propellent

: something that propels: such as

a

: an explosive for propelling projectiles

b

: fuel plus oxidizer used by a rocket engine

c

: a gas kept under pressure in a bottle or can for expelling the contents when the pressure is released

Examples of propellant in a Sentence

Recent Examples on the Web

Adjective

After liftoff from the Vandenberg Space Force Base in California on May 27, the vehicle successfully reached the Earth's orbit, but an apparent propellant leak caused a loss of altitude. —Escher Walcott, PEOPLE, 14 Oct. 2025

Conventional engines burn fuel in a steady process, where the flame front (the area at which combustion occurs) moves smoothly through a propellant mixture to produce continuous thrust. —Josh Dinner, Space.com, 16 Sep. 2025

Noun

One where exhaust and propellant residues react with ozone, thinning the layer that shields life below. —New Atlas, 25 Oct. 2025

The Tianque-12A employs liquid methane and liquid oxygen (LOX) propellants — a key difference with the Falcon 9, whose Merlin engines burn LOX and rocket-grade kerosene. —Mike Wall, Space.com, 21 Oct. 2025

Word History

Etymology

Adjective

borrowed from Latin prōpellent-, prōpellens, present participle of prōpellere "to push or thrust forward, compel to go onward" — more at propel

Noun

in part noun derivative of propellant entry 1, in part from propel + -ant entry 1

First Known Use

Adjective

1644, in the meaning defined above

Noun

1654, in the meaning defined above

Rhymes for propellant

• appellant
• libellant
• repellant
• repellent

Kids Definition

propellant

noun

pro·​pel·​lant

variants also propellent

prə-ˈpel-ənt

: something that propels: as

a

: fuel plus a chemical to supply oxygen used by a rocket engine

b

: a gas under pressure in a can for expelling the contents when the pressure is released