momentum
Americannoun
plural
momenta, momentums-
force or speed of movement; impetus, as of a physical object or course of events.
The car gained momentum going downhill. Her career lost momentum after two unsuccessful films.
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Also called linear momentum. Mechanics. a quantity expressing the motion of a body or system, equal to the product of the mass of a body and its velocity, and for a system equal to the vector sum of the products of mass and velocity of each particle in the system.
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Philosophy. moment.
noun
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p. physics the product of a body's mass and its velocity See also angular momentum
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the impetus of a body resulting from its motion
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driving power or strength
plural
momenta-
A vector quantity that expresses the relation of the velocity of a body, wave, field, or other physical system, to its energy. The direction of the momentum of a single object indicates the direction of its motion. Momentum is a conserved quantity (it remains constant unless acted upon by an outside force), and is related by Noether's theorem to translational invariance. In classical mechanics, momentum is defined as mass times velocity. The theory of Special Relativity uses the concept of relativistic mass. The momentum of photons, which are massless, is equal to their energy divided by the speed of light. In quantum mechanics, momentum more generally refers to a mathematical operator applied to the wave equation describing a physical system and corresponding to an observable; solutions to the equation using this operator provide the vector quantity traditionally called momentum. In all of these applications, momentum is sometimes called linear momentum.
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See also angular momentum impulse
Discover More
Figuratively, momentum can refer to the tendency of a person or group to repeat recent success: “The Bears definitely have momentum after scoring those last two touchdowns.”
Etymology
Origin of momentum
First recorded in 1690–1700; from Latin mōmentum; moment
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Having gone 10 Premier League matches without a win, West Ham appear to have built some momentum from Callum Wilson's dramatic late goal at Tottenham on 17 January.
From BBC
If Palmer can now build momentum, he will be hitting form at just the right time.
From BBC
“We feel very good about the momentum on Boulder Canyon,” Utz Brands CEO Howard Friedman said in a recent investor presentation.
From MarketWatch
Once-popular momentum trades that showered investors with outsize rewards last year finally hit the skids.
From MarketWatch
Even so, China’s momentum is a source of concern for U.S. policymakers and tech leaders.
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.