Aura \Au"ra\, n.; pl. Aur[ae]. [L. aura air, akin to Gr. ?.]

1. Any subtile, invisible emanation, effluvium, or exhalation from a substance, as the aroma of flowers, the odor of the blood, a supposed fertilizing emanation from the pollen of flowers, etc.

2. (Med.) The peculiar sensation, as of a light vapor, or cold air, rising from the trunk or limbs towards the head, a premonitory symptom of epilepsy or hysterics.

Electric aura, a supposed electric fluid, emanating from an electrified body, and forming a mass surrounding it, called the electric atmosphere. See Atmosphere, 2.

Source: Webster's Revised Unabridged Dictionary (1913)