名词

1. 昏迷
Someone who is in a coma is in a state of deep unconsciousness.

1. a state of deep and often prolonged unconsciousness
usually the result of disease or injury

Synonym: comatoseness

2. (astronomy) the luminous cloud of particles surrounding the frozen nucleus of a comet
forms as the comet approaches the sun and is warmed

3. (botany) a usually terminal tuft of bracts (as in the pineapple) or tuft of hairs (especially on certain seeds)