kinetic energy

American  

[ki-net-ik en-er-jee, kahy-net-ik] / kɪˈnɛt ɪk ˈɛn ər dʒi, kaɪˈnɛt ɪk /

noun

Physics.

1. the energy of a body or a system with respect to the motion of the body or of the particles in the system.

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kinetic energy British  

noun

1.  Ek.   K.   T.   KE.  the energy of motion of a body, equal to the work it would do if it were brought to rest The translational kinetic energy depends on motion through space, and for a rigid body of constant mass is equal to the product of half the mass times the square of the speed. The rotational kinetic energy depends on rotation about an axis, and for a body of constant moment of inertia is equal to the product of half the moment of inertia times the square of the angular velocity. In relativistic physics kinetic energy is equal to the product of the increase of mass caused by motion times the square of the speed of light. The SI unit is the joule but the electronvolt is often used in atomic physics

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kinetic energy Scientific  

/ kə-nĕt′ĭk /

1. The energy possessed by a system or object as a result of its motion. The kinetic energy of objects with mass is dependent upon the velocity and mass of the object, while the energy of waves depends on their velocity, frequency, and amplitude, as well as the density of the medium if there is one (as with ocean waves).

2. Compare potential energy

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kinetic energy Cultural  

1. The energy an object has because of its motion.

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Etymology

Origin of kinetic energy

First recorded in 1865–70

Compare meaning

How does kinetic-energy compare to similar and commonly confused words? Explore the most common comparisons:

• kinetic energy vs. potential energy

Example Sentences

See Examples For:

kinetic energy

In less than four seconds—according to butterflies let loose in my stomach—the Bentley swept past 60 mph, casually acquiring a kinetic energy of nearly one megajoule, roughly equivalent to a stick of dynamite.

From The Wall Street Journal ● Jul. 18, 2026

B-net is temporary and closer to webbing that’s aimed at absorbing the kinetic energy of a falling skier.

From Los Angeles Times ● Feb. 15, 2026

According to the authors, the kinetic energy associated with earthquakes can influence both the chemistry and the biological makeup of aquifer fluids.

From Science Daily ● Nov. 25, 2025

It is his sprinting prowess in particular that his rivals pinpoint as a defining factor, with the higher approach speed generating greater kinetic energy and creating the foundation for greater heights.

From BBC ● Sep. 15, 2025

It keeps spinning faster—all that kinetic energy forced down the neck of the funnel until it’s blaring like an alarm—then it falls silent as it drops into the black abyss of the funnel.

From "Challenger Deep" by Neal Shusterman