coma
UK: ˈkəʊmə | US: ˈkoʊmə
n. a state of prolonged unconsciousness, often caused by illness or injury
n. (astronomy) the diffuse, gaseous envelope surrounding the nucleus of a comet
The word "coma" traces back to the Greek koma (κῶμα), meaning "deep sleep" or "trance." It entered Late Latin as coma, retaining its medical connotation of unconsciousness. The astronomical sense emerged later, likening the hazy cloud around a comet's nucleus to a "sleeping" or shrouded state. The morpheme com- preserves the original Greek root, while -a serves as a nominalizing suffix.
The patient remained in a coma for three weeks after the accident.
Doctors are monitoring his brain activity to predict when he might wake from the coma.
The comet’s coma glowed brightly as it approached the sun.
Prolonged coma can lead to muscle atrophy and other complications.
Ancient astronomers described the coma of comets as "hairy stars" due to their fuzzy appearance.