What does "coma" mean?

Coma: (Astron.) The envelope of a comet; a nebulous covering, which surrounds the nucleus or body of a comet.

Additional senses

  1. 2.(Bot.) A tuft or bunch, -- as the assemblage of branches forming the head of a tree; or a cluster of brachts when empty and terminating the inflorescence of a plant; or a tuft of long hairs on certain seeds. Coma Berenices ( Etym: [L.] (Astron.), a small constellation north of Virgo; -- called also Berenice's Hair.

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