momentumnoun [ U ]
uk/məˈmen.təm/us/məˈmen.t̬əm/C2 the force that keeps an object moving or keeps an event developing after it has started:
Once you push it, it keeps going under its own momentum.
 The spacecraft will fly around the earth to gain/gather momentum for its trip to Jupiter.
 The play loses momentum (= becomes less interesting, energetic, etc.) by its half way stage.
 In an attempt to give new momentum to their plans, the committee set a date for starting detailed discussions.
More examples
- The campaign has been gaining momentum ever since the television appeal.
 - Opposition to the tax has been gaining momentum.
 - We got up the hill through sheer momentum.
 - The campaign for an elected mayor seems to have lost momentum.
 
Thesaurus: synonyms and related words
Physics: particular theories & concepts
- chaos theory
 - cryogenics
 - dark matter
 - Doppler effect
 - dynamics
 - element
 - kinetics
 - locomotive
 - Planck's constant
 - quantum
 - refraction
 - relativity
 - space-time
 - spring constant
 - string theory
 - time warp
 - wormhole
 
You can also find related words, phrases, and synonyms in the topics:
Speed of motion