coma: Meaning and Definition of

co•ma

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

co•ma

1. the nebulous envelope around the nucleus of a comet.
2. 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.
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.