Dictionary
im•pe•tus
Pronunciation: (im'pi-tus), [key]—
n.,
—pl. -tus•es.
1. a moving force; impulse; stimulus:
The grant for building the opera house gave impetus to the city's cultural life.
2. (broadly) the momentum of a moving body, esp. with reference to the cause of motion.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.