Definition of: impulse

(im′puls) noun
1. An impelling force, especially one that acts suddenly and produces motion; impulsion.
2. The motion produced by a sudden impelling force; impetus.
3. A sudden or transient mental urge resulting in undeliberated action, caused by the feelings or by some objective stimulus.
4. Any natural, unreasoned motive or tendency to act: a kind impulse.
5. An instinctive or reactive craving for action; a desire to act resulting from instantaneous judgments as to how to meet an emergency.
6. Physiol. A stimulus.
7. Mech. A great force acting for a very short time; also, the momentum due to a force.
8. Electr. A surge of current flowing in one direction. [<L impulsus, pp. of impellere. See IMPEL.] Synonyms: feeling, force, impetus, incentive, incitement, influence, instigation, motive. See INFLUENCE.