Most projectile weapons use the compression or expansion of gases as their motive force. Blowguns and pneumatic rifles use compressed gases, while most other guns and cannons utilize expanding gases liberated by sudden chemical reactions by propellants like smokeless powder.
A projectile is any object that once projected or dropped continues in motion by its own inertia and is influenced only by the downward force of gravity. By definition, a projectile has a single force that acts upon it - the force of gravity.
Define projectile. projectile synonyms, projectile pronunciation, projectile translation, English dictionary definition of projectile. n. 1. A fired, thrown, or otherwise propelled object, such as a bullet, having no capacity for self-propulsion. 2. A self-propelled missile, such as a...