Definition of: corona

(kə·rō′nə) noun plural ·nas or ·nae (-nē)
1. A garland or wreath given by the ancient Greeks and Romans as a reward for distinguished achievements.
2. Archit. The projecting brow of a cornice.
3. A crownlike part, structure, or process, as the crown of the head or the shell of a sea–urchin.
4. Astron. a A luminous circle around one of the heavenly bodies. b The luminous envelope of ionized gases surrounding the chromosphere of the sun and visible during a total eclipse.
5. Loosely, any halo.
6. Electr. The luminous discharge at the surface of an electrical conductor under very high voltage.
7. Bot. A crownlike process at the top of the tube of the corolla, as in jonquils.
8. Geol. A zone of minerals surrounding another mineral or at the junction of two minerals. [<L, crown]