Simple Definition of miasma
: a heavy cloud of something unpleasant or unhealthy
Full Definition of miasma
1 : a vaporous exhalation formerly believed to cause disease; also : a heavy vaporous emanation or atmosphere <a miasma of tobacco smoke>
2 : an influence or atmosphere that tends to deplete or corrupt <freed from the miasma of poverty — Sir Arthur Bryant>; also : an atmosphere that obscures : fog
Did You Know?
In notes taken during a voyage to South America on HMS Beagle in the 1830s, Charles Darwin described an illness that he believed was caused by "miasma" emanating from stagnant pools of water. For him, "miasma" had the same meaning that it did when it first appeared in English in the 1600s: an emanation of a vaporous disease-causing substance. ("Miasma," by the way, comes from Greek miainein, meaning "to pollute.") But while Darwin was at sea, broader applications of "miasma" were starting to spread. Nowadays, we know germs are the source of infection, so we're more likely to use the newer, more figurative sense of "miasma," which refers to something destructive or demoralizing that surrounds or permeates.
Origin of miasma
New Latin, from Greek, defilement, from miainein to pollute
First Known Use: 1665
Medical Definition of miasma
plural miasmas also miasmata \-mət-ə\play
: a vaporous exhalation (as of a marshy region or of putrescent matter) formerly believed to cause disease (as malaria)
Seen and Heard
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