Learner's definition of IMPETUS
1
: a force that causes something (such as a process or activity) to be done or to become more active推动;促进;刺激 [noncount]
[singular]
—
often + for —
sometimes followed by to + verb有时接动词不定式 2
[noncount] technical : a force that causes an object to begin moving or to continue to move动力;动能