pro·​pel·​lant | \ prə-ˈpe-lənt How to pronounce propellant (audio) \
variants: or less commonly propellent

Definition of propellant

 (Entry 1 of 2)

: capable of propelling


variants: or less commonly propellent

Definition of propellant (Entry 2 of 2)

: 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 The launch was originally scheduled for Wednesday night, but that attempt was scrubbed due to a propellant temperature issue., 2 July 2022 Of the main propellant types in use today, only hydrogen fueled rockets do not emit black carbon, says Maloney. Bruce Dorminey, Forbes, 17 June 2022 The Starship-Super Heavy launch vehicle, seen here during propellant loading tests, stands 400 feet tall and measures 30 feet wide. William Harwood, CBS News, 13 June 2022 In 2012 several billionaire entrepreneurs founded a company called Planetary Resources with the goal of harvesting water from asteroids and selling it as propellant at in-space fuel depots. Eric Berger, Ars Technica, 31 May 2022 The technology would allow a craft to travel farther with less propellant than today’s chemical rocket systems. Manasee Wagh, Popular Mechanics, 11 May 2022 Now, teams of NASA employees and contractors will be called to their stations again on Tuesday evening to prepare the vehicle and ground systems for propellant loading for the third time. Eric Berger, Ars Technica, 12 Apr. 2022 Originally scheduled for February, the rehearsal was delayed once for further testing and then again for issues involving propellant loading. Zoe Sottile And Ross Levitt, CNN, 9 Apr. 2022 This would provide a huge mass and propellant savings on each spacecraft. Eric Berger, Ars Technica, 1 Dec. 2021 Recent Examples on the Web: Noun In 2017, the company launched its first satellite powered by a sustainable propellant system the company developed in-house. Alex Knapp, Forbes, 5 July 2022 Thanks to a precise launch by the European Space Agency's Ariane 5 rocket, Webb should have enough maneuvering propellant on board for 20 years of life. Eric Berger, Ars Technica, 29 June 2022 When this happens, the propellant briefly forms a cloud in space. Joshua Hawkins, BGR, 20 June 2022 Novelty was a propellant, a reason to reach the end of each day faster. Gloria Liu, The Atlantic, 21 Apr. 2022 After days of trying to fix the problem, Boeing rolled the spacecraft back into the factory and discovered that propellant seeping through a valve mixed with moisture in the air to create nitric acid. Christian Davenport, Washington Post, 19 May 2022 At this point, the process is similar to other rockets, in which gas propellant expands and shoots through a nozzle, thrusting the aircraft away. Manasee Wagh, Popular Mechanics, 11 May 2022 Long-simmering hostility toward Moscow and its historical subjugation of Eastern Europe is the propellant that has driven the continent’s most successful energy-independence movements. Washington Post, 6 May 2022 However, because of the propellant spent during these activities, Starliner was unable to complete its primary objective, demonstrating a safe docking with the International Space Station. Eric Berger, Ars Technica, 4 May 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'propellant.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of propellant


1644, in the meaning defined above


1654, in the meaning defined above

History and Etymology for propellant


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


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

Learn More About propellant

Time Traveler for propellant

Time Traveler

The first known use of propellant was in 1644

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Last Updated

11 Jul 2022

Cite this Entry

“Propellant.” Dictionary, Merriam-Webster, Accessed 9 Aug. 2022.

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