miasma

Everyday

1. A cloud of bad-smelling, unhealthy air, such as the smell from rotting things or a swamp. tree →
2. (figurative) A heavy, unpleasant feeling that hangs over a place: «a miasma of gloom». tree →
3. (history of science) The old wrong idea that diseases like cholera were caused by «bad air» (miasma), before germs were discovered. tree →

In the lessons

In history and science lessons, «miasma theory» was believed until the 1800s; John Snow's work on cholera in London in 1854 and later germ theory (Pasteur, Koch) showed diseases are spread by germs, not smells. In stories, a miasma hangs over swamps, dungeons or sad places. Phrases: «a miasma of smoke», «miasma theory».

Examples

• A miasma rose from the rotting swamp. tree →
• People once blamed cholera on miasma, or bad air. tree →
• John Snow showed that dirty water, not miasma, spread cholera. tree →
• A miasma of cigarette smoke filled the old pub. tree →
• A miasma of sadness hung over the empty house. tree →
• Miasma theory was replaced by germ theory. tree →
• The dragon's cave was full of a foul miasma. tree →
• Florence Nightingale also believed in miasma, but her cleaning still saved lives. tree →

Note

Countable: one miasma, two miasmas. Pronounced «mee-AZ-ma» or «my-AZ-ma». Myth trap: bad smells do not cause diseases themselves; germs do (though rotting things can contain germs). Not a maths word.