Definition of corona
noun (plural coronae /-nē, -nī/)
1 Astronomy the rarefied gaseous envelope of the sun and other stars. The sun’s corona is normally visible only during a total solar eclipse when it is seen as an irregularly shaped pearly glow surrounding the darkened disk of the moon. (also corona discharge) Physics the glow around a conductor at high potential. a small circle of light seen around the sun or moon, due to diffraction by water droplets.
2 Anatomy a crown or crownlike structure. Botany the cup-shaped or trumpet-shaped outgrowth at the center of a daffodil or narcissus flower.
3a circular chandelier in a church.
4 Architecture a part of a cornice having a broad vertical face.