1. The act of impelling or the condition of being impelled: "I do not move ... unless it be under the impulsion of a third party" (Samuel Beckett).
2. An impelling force; a thrust.
3. Motion produced by an impelling force; momentum.
4. A wish or urge from within; an impulse.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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