I. ˈimˌpəls also -lts noun
Etymology: Latin impulsus, from impulsus, past participle of impellere to impel — more at impel
1.
a. : the act of driving onward with sudden force : impulsion , thrust , drive , push
b. : the effect of an impelling force : motion produced by a sudden or momentary force : impetus
the impulse of the pumping by the heart is carried down so that a finger applied to the artery anywhere near the surface permits a counting of the pulse rate — Morris Fishbein
c. : a wave of excitation transmitted through certain tissues and especially nerve fibers and muscles that results in physiological activity or inhibition
d. : an electrical or mechanical action or force usually of brief duration
the impulses received by the radio set are … unimaginably small — A.C.Morrison
specifically : such an action or force actuating an operation (as in a computer)
can be started either by hand or by an air impulse — Swiss Industry & Trade
2.
a. : a force so communicated as to produce motion suddenly or immediately
an impulse of the wind
(1) : the motive force given by the escape wheel in the driving train of a timepiece to the pendulum or balance
(2) : the muscular effort initiating a rhythmic dance movement
(3) : a short directed motion
written with one impulse of the pen — J.R.Gregg
b. : incentive
under the impulse of transportation profits — American Guide Series: Michigan
c. : an inspiration or motivation especially giving a usually new form or tendency
those who give the religious life a new impulse need disciples to organize the impulse before it runs to seed — Hallam Tennyson
his more successful stories derive from the same kind of impulse as his poetry — F.R.Leavis
he received from America fresh artistic impulses — Anatole Chujoy
3.
a. : a sudden spontaneous inclination or an incitement of the mind or spirit arising either directly from feeling or from some outer influence and prompting some usually unpremeditated action
constitutionally inclined to resist impulse and to take long views — George Santayana
some uncontrollable impulse … may have driven the defendant to the commission of the murderous act — B.N.Cardozo
act on impulse
also : the force actuated by such a motive or propensity
a man who is driven chiefly by impulse
impulses of greed — Bertrand Russell
b. : a propensity or natural tendency usually other than rational
a man of good impulses
the sexual impulse
the fundamental impulse of self-expression — Havelock Ellis
the systematizing impulse , the restless passion for order of the Greeks — John Buchan
never approaches a new task save with the impulse to postpone it — H.A.Overstreet
4.
a. : the product of the average value of a force and the time during which it acts being a quantity equal to the change in momentum produced by the force if the body acted on is free
b. : pulse 4a
Synonyms: see motive
II. “, ə̇mˈp- transitive verb
Etymology: Latin impulsus, past participle
1. : to give an impulse to
2. : to initiate an impulse in (a counter of a computer)