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1. A state of deep and often prolonged unconsciousness; usually the result of disease or injury
   - comatoseness
    
2. (botany) a usually terminal tuft of bracts (as in the pineapple) or tuft of hairs (especially on certain seeds)
    
3. (astronomy) the luminous cloud of particles surrounding the frozen nucleus of a comet; forms as the comet approaches the sun and is warmed
    
4. (optics) an aberration giving a V-shaped flare to an image (e.g. a star in an astronomical observation)

Derived forms: comae, comas

Type of: cloud, tuft, tussock, unconsciousness

Part of: comet

Encyclopedia: Coma, post-head injury