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

“It’s a step change in simulating things like kinetic energy and gravity,” Hassabis says.

From The Wall Street Journal • May 19, 2026

The 2.4-litre V8s used in 2013 weighed 130kg, including the small kinetic energy recovery systems used then and batteries.

From BBC • May 14, 2026

“It doesn’t just stop a blade. It spreads the kinetic energy across the fabric. The yards can work almost like a conveyor belt, preventing energy from concentrating at a single point.”

From Los Angeles Times • Feb. 15, 2026

Their momentum spread out again, kinetic energy increased rapidly, and the system resumed absorbing energy without limit.

From Science Daily • Jan. 8, 2026

I’m that coin on its way down, screaming in the neck of the funnel, with nothing but my own kinetic energy and centrifugal force keeping me from dropping into darkness.

From "Challenger Deep" by Neal Shusterman