tr.v. dis·turbed, dis·turb·ing, dis·turbs
1. To break up or destroy the tranquility, order, or settled state of: “Subterranean fires and deep unrest disturb the whole area” (Rachel Carson).
2. To trouble emotionally or mentally; upset: It disturbed me when you left without saying goodbye.
a. To interfere with; interrupt: noise that disturbed my sleep.
b. To intrude on; inconvenience: Constant calls disturbed her work.
4. Physics To alter or displace (one or more properties of a physical system) away from its equilibrium state.
[Middle English distourben, from Old French destourber, from Latin disturbāre : Latin dis-, dis- + Latin turbāre, to agitate (from turba, confusion, probably from Greek turbē).]
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:
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