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n. pl. mi·as·mas or mi·as·ma·ta (-mə-tə)
1. A noxious atmosphere or influence: "The family affection, the family expectations, seemed to permeate the atmosphere ... like a coiling miasma" (Louis Auchincloss).
a. A foul-smelling vapor arising from rotting organic matter, formerly thought to cause disease.
b. A thick vaporous atmosphere or emanation: wreathed in a miasma of cigarette smoke.
[Greek, pollution, stain, from miainein, to pollute.]
mi·as′mal, mi′as·mat′ic (mī′əz-măt′ĭk), mi·as′mic (-mĭk) adj.
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.