What does "degeneration" mean?

Degeneration: (Physiol.) That condition of a tissue or an organ in which its vitality has become either diminished or perverted; a substitution of a lower for a higher form of structure; as, fatty degeneration of the liver.

Additional senses

  1. 2.(Biol.) A gradual deterioration, from natural causes, of any class of animals or plants or any particular or organs; hereditary degradation of type.
  2. 3.The thing degenerated. [R.] Cockle, aracus, . . . and other degenerations. Sir T. Browne. Amyloid degeneration, Caseous degeneration, etc. See under Amyloid, Caseous, etc.

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