English Reference
noun

propulsion

n.
US /pɹəˈpəɫʃən/ UK /pɹəpˈʌlʃən/ propul·sion UK spelling propulsion's, propulsion's

  1. 01 C1 Advanced Technical Science

    the force or process that moves an object forward.

    the action of driving or pushing forward; the process of propelling an object through a medium.

    Simple

    The rocket uses powerful engines for propulsion to reach space.

    In context

    The spacecraft relies on ion propulsion for long-distance travel, as it is far more fuel-efficient than traditional chemical rockets.

    Usage

    Often used as an uncountable noun when referring to the general concept of movement.

  2. 02 C1 Advanced Technical Computing

    a specific system or engine that makes a vehicle move.

    a specific mechanism or system, such as an engine or motor, that provides the force for movement.

    Simple

    The ship's main propulsion failed, leaving the crew stuck at sea.

    In context

    Engineers are developing a new nuclear propulsion system that could significantly reduce the time required for a manned mission to Mars.

    power plantengine

Simplifying the steering system was an important part of achieving that size while retaining propulsion based on photon recoil.

ScienceDaily· 18 Aug 2026

It seems like there’s nothing that is preventing us from reestablishing three-axis control of the spacecraft with the remaining reaction wheel, with the remaining thrusters, as well as the electric propulsion.

Ars Technica· 1 Aug 2026

Borrowed from Medieval Latin propulsio, propulsionis, from the past participle of Latin propello (“to drive forward, drive forth, drive away, drive out”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin propello
Level C1 · Advanced
Frequency Frequent
Updated