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1. Quiet, still, or inactive. See Synonyms at inactive.
2. Characterized by an absence of upheaval or discord: "We tend to think of the decades following the final overthrow of Napoleon as remarkably quiescent" (Walter McDougall).
3. Astronomy Having little or no sunspot activity.
4. Medicine Asymptomatic: a quiescent infection.
[Latin quiēscēns, quiēscent-, present participle of quiēscere, to rest, from quiēs, quiet; see quiet.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.