a. The act of compelling.
b. The state of being compelled.
2. An irresistible impulse to act, regardless of the rationality of the motivation: "He felt an animal compulsion to flee the hotel and the city" (Paul Theroux).
3. Psychiatry An act or ritual that a person feels compelled to perform repeatedly, often to reduce the distress caused by an obsession.
[Middle English, from Old French, from Late Latin compulsiō, compulsiōn-, from Latin compulsus, past participle of compellere, to compel; see COMPEL.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.