Coma

n.
  1. (Astron.) The envelope of a comet; a nebulous covering, which surrounds the nucleus or body of a comet.
  2. (Bot.) 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.
    3. Coma Berenices () (Astron.),
    a small constellation north of Virgo; -- called also Berenice's Hair.