momentum

noun

1. the product of a body's mass and its velocity

e.g. the momentum of the particles was deduced from meteoritic velocities

2. an impelling force or strength

e.g. the car's momentum carried it off the road

Synonym: impulse

1. 势头;冲劲;动力
If a process or movement gains momentum, it keeps developing or happening more quickly and keeps becoming less likely to stop.

e.g. This campaign is really gaining momentum...
该运动的势头越来越猛。
e.g. They are each anxious to maintain the momentum of the search for a solution.
他们每个人都迫切希望能一直劲头十足地去寻求解决方案。

2. (物理学中的)动量，冲量
In physics, momentum is the mass of a moving object multiplied by its speed in a particular direction.