impulsen.[L. impulsus, fr. impellere. See Impel.]()1. The act of impelling, or driving onward with sudden force; impulsion; especially, force so communicated as to produced motion suddenly, or immediately.()All spontaneous animal motion is performed by mechanical impulse. (S. Clarke.)2. The effect of an impelling force; motion produced by a sudden or momentary force.()3. (Mech.) The action of a force during a very small interval of time; the effect of such action; as, the impulse of a sudden blow upon a hard elastic body.()4. A mental force which simply and directly urges to action; hasty inclination; sudden motive; momentary or transient influence of appetite or passion; propension; incitement; as, a man of good impulses; passion often gives a violent impulse to the will; to buy something on impulse.()These were my natural impulses for the undertaking. (Dryden.)()v. t.[See Impel.] To impel; to incite.(Pope.)