impulse

an instinctive motive; "profound religious impulses"

a sudden desire; "he bought it on an impulse"

the electrical discharge that travels along a nerve fiber; "they demonstrated the transmission of impulses from the cortex to the hypothalamus"

(electronics) a sharp transient wave in the normal electrical state (or a series of such transients); "the pulsations seemed to be coming from a star"

the act of applying force suddenly; "the impulse knocked him over"

an impelling force or strength; "the car's momentum carried it off the road"