coma

Meanings

1. 1
   noun

   a state of deep and often prolonged unconsciousness

   After the accident, I was in a coma for three weeks.

2. 2
   noun

   the luminous cloud of particles surrounding the frozen nucleus of a comet

   The comet was so close, you could see the coma during the day.

3. 3
   noun

   a usually terminal tuft of bracts, such as in the pineapple, or tuft of hairs, especially on certain seeds

   The cotton plant has a coma on its seed.

4. 4
   noun

   A state of unconsciousness from which one may not wake up, usually induced by some form of trauma.

   go into a coma

5. 5
   noun

   A cloud of dust surrounding the nucleus of a comet.

6. 6
   noun

   A defect characterized by diffuse, pear-shaped images that in an ideal image would appear as points.

7. 7
   noun

   A tuft or bunch, such as the assemblage of branches forming the head of a tree, a cluster of bracts when empty and terminating the inflorescence of a plant, or a tuft of long hairs on certain seeds.

Etymology

Learned borrowing from Latin coma (“hair of the head”), from Ancient Greek κόμη (kómē, “hair”).