What does corona mean?
A corona is a crown — literally, in its original Latin sense, and figuratively in most modern uses. In astronomy, it refers above all to the sun's outermost atmospheric layer, a vast envelope of hot plasma normally hidden by the sun's glare but revealed as a shimmering, pearl-white halo during a total solar eclipse. By extension, the word describes any circular glow or halo around a light source, such as the faint ring sometimes seen around the moon. In other fields, corona retains its crown-like sense: botanists use it for the trumpet-shaped or crown-like part of certain flowers, notably the daffodil, while physicists speak of a corona discharge — a faint electrical glow around a charged conductor. Derived from Latin corona meaning 'garland' or 'wreath,' the word underlies related terms such as coronation, coronet, and even coronavirus, named for the crown-shaped spikes projecting from the virus's surface. Its plural is coronas in general use, or coronae in technical writing.
The outermost part of the sun's atmosphere, visible as a white halo during a total solar eclipse; by extension, any similar ring or halo of light around a luminous body.
"The corona stretched millions of kilometres into space, far beyond the visible disk of the sun."
A crown or something shaped like a crown, such as the crown-like part of a flower or a ring-shaped structure in anatomy or physics.
"Each daffodil bears a central cup called the corona, which gives the flower its distinctive trumpet form."
This broader sense covers specialized uses in botany, anatomy, and physics (e.g., corona discharge).
'Coronas' is the standard plural in general English; 'coronae' survives in scientific and astronomical contexts, following the Latin pattern.
"Photographers captured several images of solar coronas during the eclipse expeditions."
The same Latin word for 'crown' that names the sun's glowing halo also gave us 'coronation' — and eventually, 'coronavirus', named for the virus's crown-like spikes.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of corona
Corona comes directly from Latin, where it meant a garland, wreath, or crown, ultimately from Greek korōnē ('curved object, crown'). English adopted the word in the early modern period, initially for crowns and crown-shaped things before extending it to circles of light around celestial bodies. It shares this root with cognates and derivatives including crown, coronet, corolla, corollary, and coronary, all reflecting the underlying idea of a curved or encircling shape.
Related word forms
How corona is actually used
In scientific writing, 'the corona' almost always refers specifically to the sun's outer atmosphere. In everyday speech since 2020, the clipped form 'the corona' has occasionally been used informally as shorthand for coronavirus, though this is informal and context-dependent. The plural is usually 'coronas' in general use, but 'coronae' persists in technical and astronomical contexts.
Easily confused with corona
A chorus is a group of singers or a repeated refrain, whereas a corona is a crown-like circle of light or a crown itself.
A corolla is the collective petals of a flower, while a corona is a crown or a ring of light around a celestial body.