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rev·o·lu·tion (rĕvə-lshən)
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n.
1.
a. Orbital motion about a point, especially as distinguished from axial rotation: the planetary revolution about the sun.
b. A turning or rotational motion about an axis.
c. A single complete cycle of such orbital or axial motion.
2. The overthrow of one government and its replacement with another.
3. A sudden or momentous change in a situation: the revolution in computer technology.
4. Geology A time of major crustal deformation, when folds and faults are formed.

[Middle English revolucioun, from Old French revolution, from Late Latin revolūtiō, revolūtiōn-, from Latin revolūtus, past participle of revolvere, to turn over; see REVOLVE.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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