coma
coma Lexical Profile
coma Game Scores & Validity
• noun
A prolonged state of deep unconsciousness, caused especially by severe injury, illness, or poison, in which a person cannot be awakened and fails to respond normally to painful stimuli, light, or sound.
"The patient remained in a medically induced coma for several days while the swelling in his brain subsided."
A luminous, nebulous envelope of gas and dust that forms around the nucleus of a comet as it approaches the sun and warms.
"Through the backyard telescope, the amateur astronomer clearly observed the bright coma surrounding the icy nucleus of the approaching comet."
An optical aberration in lenses or curved mirrors in which off-axis point sources of light, such as stars, appear distorted with a comet-like flare or tail.
"Parabolic telescope mirrors often suffer from coma near the edges of the field of view unless a corrective lens is installed."
In botany, a tuft of silky hairs attached to the end of certain seeds, such as milkweed, or a leafy crown at the top of a plant or fruit, such as a pineapple.
"The feathery coma attached to each milkweed seed allows it to be carried great distances by autumn breezes."
Word Nuance & Usage
Do not confuse 'coma' (a state of deep unconsciousness, or the nebulous envelope of a comet) with 'comma' (the punctuation mark). Notably, the two words have distinct Greek roots: the medical sense derives from 'kōma' (deep sleep), whereas the astronomical and optical senses derive from 'komē' (hair).
• Rhymes for coma
Word Origin & Etymology
The medical sense entered English in the mid-17th century via Modern Latin from Ancient Greek 'kōma', meaning 'deep sleep'. The astronomical and botanical senses come independently from Latin 'coma', borrowed from Ancient Greek 'komē', meaning 'hair of the head' (whence also 'comet').