momentum

noun

mo·​men·​tum mō-ˈmen-təm 

mə-

plural momenta mō-ˈmen-tə 

mə-

or momentums

1

: a property (see property sense 1a) of a moving body that the body has by virtue of its mass (see mass entry 2 sense 1c) and motion and that is equal to the product of the body's mass and velocity

broadly : a property of a moving body that determines the length of time required to bring it to rest when under the action of a constant force or moment

2

: strength or force gained by motion or by a series of events

The wagon gained momentum as it rolled down the hill.

Synonyms of momentum

• impetus
• incentive
• encouragement
• motivation
• stimulus

Examples of momentum in a Sentence

The company has had a successful year and hopes to maintain its momentum by introducing new products.

The movie loses momentum toward the end.

Recent Examples on the Web

Dutch find separating goal to regain control With Japan in full control of momentum after the quick answer, the Netherlands parlayed a swing of possession into a winner in the 64th minute. —Nick Harris, Fort Worth Star-Telegram, 15 June 2026

Say it clearly, and let momentum reward your clarity today. —Tarot.com, Sun Sentinel, 15 June 2026

The momentum from a strong auction season last November carried into the May sales, led by Christie’s $181 million sale of a Jackson Pollock painting. —Devorah Lauter, ARTnews.com, 15 June 2026

The first season spun its wheels, got cool, squandered the momentum with a time jump, threatened to get cool by the end, and squandered the momentum again with a gap between seasons. —Daniel Fienberg, HollywoodReporter, 15 June 2026

Word History

Etymology

New Latin, from Latin, movement

First Known Use

1610, in the meaning defined at sense 1

Phrases Containing momentum

• angular momentum
• gather/gain momentum
• gather momentum/strength
• lose momentum
• pick up speed/momentum

Rhymes for momentum

• cementum
• omentum
• tegmentum
• tomentum
• argumentum
• sacramentum
• testamentum
• centum
• mentum

Kids Definition

momentum

noun

mo·​men·​tum mō-ˈment-əm 

plural momenta -ˈment-ə  or momentums

1

: the characteristic of a moving body that is caused by its mass and its motion

2

: impetus sense 1

Medical Definition

momentum

noun

mo·​men·​tum mō-ˈment-əm, mə-ˈment- 

plural momenta -ˈment-ə  or momentums

: a property of a moving body that the body has by virtue of its mass and motion and that is equal to the product of the body's mass and velocity

broadly : a property of a moving body that determines the length of time required to bring it to rest when under the action of a constant force