momentum

Momentum is generally used to mean increasing forward motion. A boulder rolling down a hill gains momentum. So does a great idea, a team on a winning streak, or the economy.

To find an object's physical momentum you multiply its mass by its velocity. Determining the momentum of the economy or the latest fad is much more difficult. Used figuratively, momentum implies that, like a boulder rolling down a hill, something with momentum will continue moving forward on its own. If you're running for class president, you might want to build momentum by holding a few rallies, passing out flyers and starting a website. Once you have momentum, your opponents won't be able to stop you.

Definitions of momentum
  1. noun
    the product of a body's mass and its velocity
    “the momentum of the particles was deduced from meteoritic velocities”
    see moresee less
    types:
    angular momentum
    the product of the momentum of a rotating body and its distance from the axis of rotation
    type of:
    physical property
    any property used to characterize matter and energy and their interactions
  2. noun
    an impelling force or strength
    “the car's momentum carried it off the road”
    synonyms: impulse
    see moresee less
    type of:
    force, forcefulness, strength
    physical energy or intensity
Word Family
EDITOR’S CHOICE

Test prep from the experts

Boost your test score with programs developed by Vocabulary.com’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.

SAT/PSAT

$29.95
  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week

TOEFL

$29.95
  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week

ACT

$29.95
  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week