Webster's Revised Unabridged Dictionary · 1913

Coma

Coma (kō"mȧ) , noun

[New Latin, from Greek kw^ma lethargy, from koima^n to put to sleep. See Cemetery.]

A state of profound insensibility from which it is difficult or impossible to rouse a person. See Carus.

Coma , noun

[Latin, hair, from Greek ko`mh.]

1.
(Astronomy) The envelope of a comet; a nebulous covering, which surrounds the nucleus or body of a comet.
2.
(Botany) A tuft or bunch, -- as the assemblage of branches forming the head of a tree; or a cluster of bracts when empty and terminating the inflorescence of a plant; or a tuft of long hairs on certain seeds.
Collocations (1)
Coma Berenices (Astronomy) , a small constellation north of Virgo; -- called also Berenice's Hair.