A propellant is a force or substance that drives something else forward. Your model rocket needs a propellant, or a fuel to push it into the air. You might use something as simple as vinegar and baking soda. Space rockets use solid or liquid propellants, or fuel.

Propellant derives from the word propel, which means to drive something forward with force. A propellant can be fuel, or the explosive charge that pushes a bullet out of a gun. Gases used to propel can be called "propellant gases" and might be stored in a "propellant tank." Note that some dictionaries accept the variant spelling propellent.

Definitions of propellant

n any substance that propels

rocket fuel, rocket propellant, rocket propellent
an explosive charge that propels a rocket
compressed gas
gas at a high pressure that can be used as a propellant
compressed air
air at a pressure greater than that of the atmosphere
Type of:
a particular kind or species of matter with uniform properties

adj tending to or capable of propelling

propellant fuel for submarines”
propellent, propelling, propulsive
dynamic, dynamical
characterized by action or forcefulness or force of personality

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