coma

¹ American  

[koh-muh] / ˈkoʊ mə /

noun

PLURAL

comas

1. a state of prolonged unconsciousness, including a lack of response to stimuli, from which it is impossible to rouse a person.

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coma ² American  

[koh-muh] / ˈkoʊ mə /

noun

PLURAL

comae

1. Astronomy. the nebulous envelope around the nucleus of a comet.

2. Optics. a monochromatic aberration of a lens or other optical system in which the image from a point source cannot be brought into focus, the image of a point having the shape of a comet.

3. Botany.

   1. a tuft of silky hairs at the end of a seed.

   2. the leafy crown of a tree; cluster of leaves at the end of a stem.

   3. a terminal cluster of bracts, as in the pineapple.

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coma ¹ British  

/ ˈkəʊmə /

noun

1. a state of unconsciousness from which a person cannot be aroused, caused by injury to the head, rupture of cerebral blood vessels, narcotics, poisons, etc

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coma ² British  

/ ˈkəʊmə /

noun

1. astronomy the luminous cloud surrounding the frozen solid nucleus in the head of a comet, formed by vaporization of part of the nucleus when the comet is close to the sun

2. botany

   1. a tuft of hairs attached to the seed coat of some seeds

   2. the terminal crown of leaves of palms and moss stems

3. optics a type of lens defect characterized by the formation of a diffuse pear-shaped image from a point object

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coma ¹ Scientific  

/ kō′mə /

PLURAL

comas

1. A state of deep unconsciousness, usually resulting from brain trauma or metabolic disease, in which an individual is incapable of sensing or responding to external stimuli.

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coma ² Scientific  

/ kō′mə /

PLURAL

comae

1. Astronomy The brightly shining cloud of gas that encircles the nucleus and makes up the major portion of the head of a comet near the Sun. As a comet moves along its orbit away from the Sun, the gas and dust of the coma dissipate, leaving only the nucleus. A coma can have a diameter of up to 100,000 km (62,000 mi.).

2. Astronomy See more at comet

3. Physics A diffuse, comet-shaped image of a point source of light or radiation caused by aberration in a lens or mirror. The image appears progressively elongated with distance from the center of the field of view.

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coma Cultural  

1. An abnormal state of deep unconsciousness. A coma may occur as the result of trauma to the head, disease (such as meningitis, stroke, or diabetes mellitus), or poisoning.

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Other Word Forms

• comal adjective

Etymology

Origin of coma¹

First recorded in 1640–50, coma is from the Greek word kôma deep sleep

Origin of coma¹

1660–70; < Latin: hair < Greek kómē

Example Sentences

But she’s in a coma and Hawkins is now split wide open, with particles from the Upside Down pouring in.

From Salon

Ma spent about eight months in a coma before dying as a result of the injuries he sustained in the attack.

From Seattle Times

McDermott’s childhood memories are matched by naïvely excited music; the flotation tank, by a soporific étude; the simulated coma, by music so shapeless yet alluring that it could have been written by Satie.

From New York Times

Two protesters are still in a coma after being injured in the clashes.

From New York Times

Two men are in a coma after violent clashes on Saturday between protesters and police during an unauthorised demonstration against the construction of a giant water reservoir for farm irrigation in western France.

From Reuters

Related Words

• oblivion
• slumber
• stupor
• trance