miasma

American  

[mahy-az-muh, mee-] / maɪˈæz mə, mi- /

noun

• miasmas,
  plural
• miasmata
  plural

1. noxious exhalations from putrescent organic matter; poisonous effluvia or germs polluting the atmosphere.

2. a dangerous, foreboding, or deathlike influence or atmosphere.

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miasma British  

/ mɪˈæzmə /

noun

1. an unwholesome or oppressive atmosphere

2. pollution in the atmosphere, esp noxious vapours from decomposing organic matter

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Other Word Forms

Derived Forms

• miasmal
  adjective
• miasmatic
  adjective
• miasmatical
  adjective
• miasmic
  adjective
• unmiasmal
  adjective
• unmiasmatic
  adjective
• unmiasmatical
  adjective
• unmiasmic
  adjective

Inflected Forms

Nouns

• miasmas
  plural
• miasmata
  plural

Etymology

Origin of miasma

1655–65; < New Latin < Greek míasma stain, pollution, akin to miaínein to pollute, stain

Explanation

A miasma is a cloud of foul-smelling vapor, like swamp gas. You could have a miasma of sweat that lingers in a locker room long after a soccer team has left, or a miasma of rumor swirling around a politician. As you've probably figured out, miasma is always negative. You could describe the miasma of a hot summer day, but you'd be thinking of the stench of uncollected garbage and exhaust fumes, not the smell of summer flowers. From the Middle Ages until the late 19th century, when germs were identified as causing disease, people believed that you could get sick from the miasma of everyday life — from the odors arising from poor sanitation and cramped quarters.

Example Sentences

See Examples For:

miasma miasmas miasmata

As I emerged from my children’s earliest years—a miasma of Duplo blocks, nursing pads and sleepless nights—I felt utterly depleted, not just in a physical sense but in a creative one.

From The Wall Street Journal ● Jun. 14, 2026

There’s some truth to this, but the overarching emphasis on miasma theory fundamentally ignores how the immune system works.

From Salon ● Nov. 29, 2025

In such a milieu, Hine’s troubling 1908 photographs would easily disappear, perhaps seizing a moment but soon evaporating into the visual miasma that floods the zone daily.

From Los Angeles Times ● May 5, 2025

It was a couple of weeks after the great smog had brought London to a standstill, and although that particularly foul miasma had dispersed, smog still regularly reduced visibility.

From BBC ● Dec. 30, 2024

“Doc says it’s something in the air that spreads ague—something off bad water and garbage. A miasma, he called it.”

From "Kindred" by Octavia Butler

Unlike today, when scientists know that disease is spread by microorganisms, Victorian Englishmen thought it was spread by "miasmas," or "bad air."

From Salon ● Jul. 25, 2023

Some scientists believed that diseases were the result of miasmas, or bad smells such as those produced by dead bodies, biological waste and other disease-carrying substances.

From Salon ● Feb. 26, 2022

Modern warfare creates miasmas of emotion, information, misinformation, deception and secrecy.

From The Guardian ● Sep. 8, 2018

It’s a madman’s trapezoid, a magic carpet ride of dazed miasmas and subtle brumes.

From Washington Post ● Jan. 13, 2016

Note it then, my dear Spilett; for it appears proved that the presence of the eucalyptus is enough to neutralize miasmas.

From The Mysterious Island by Jules Verne

The air, purer and less charged with miasmata and heterogeneous emanations, becomes at the same time drier.

From Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 2 by Alexander von Humboldt

The lungs thus become a ready inlet to contagion, miasmata, and other poisonous influences diffused through the air we breathe.

From Popular Education For the use of Parents and Teachers, and for Young Persons of Both Sexes by Ira Mayhew

The lake, the waters of which appear yellow by transmitted light, is dry in the season of great heat, and the Indians themselves are unable to resist the miasmata rising from the mud.

From Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 2 by Alexander von Humboldt

The beds of seaweed, in a constant state of decomposition on the Pacific shore, create miasmata unquestionably injurious to health.

From Blackwood's Edinburgh Magazine — Volume 54, No. 337, November, 1843 by Various

I believe that it is by a direct operation on the system, and not by the generation of miasmata, that heat proves so deleterious to the infant.

From North American Medical and Surgical Journal, Vol. 2, No. 3, July, 1826 by Franklin Bache