#1 corona n. [aureole] the outermost region of the sun's atmosphere; visible as a white halo during a solar eclipse. wn #2 corona n. (botany) the trumpet-shaped or cup-shaped outgrowth of the corolla of a daffodil or narcissus flower. wn #3 corona n. [corona discharge, corposant, St. Elmo's fire, Saint Elmo's fire, Saint Elmo's light, Saint Ulmo's fire, Saint Ulmo's light, electric glow] an electrical discharge accompanied by ionization of surrounding atmosphere. wn #4 corona n. one or more circles of light seen around a luminous object. wn #5 corona n. (anatomy) any structure that resembles a crown in shape. wn