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1870 in spiritualism, "subtle emanation around living beings;" earlier "characteristic impression" made by a personality (1859), earlier still "gentle breeze" (late 14c.), from Latin aura "breeze, wind, air," from Greek aura "breath, breeze," from PIE root *awer- (see air (n.1)).
aura au·ra (ôr'ə)
n. pl. au·ras or au·rae (ôr'ē)
A sensation, as of a cold breeze or a bright light, that precedes the onset of certain disorders, such as an epileptic seizure or an attack of migraine.