What does "pith" mean?

Pith: (a) (Zoöl.) The spongy interior substance of a feather. (b) (Anat.) The spinal cord; the marrow.

Additional senses

  1. 2.Hence: The which contains the strength of life; the vital or essential part; concentrated force; vigor; strength; importance; as, the speech lacked pith. Enterprises of great pith and moment. Shak. Pith paper. Same as Rice paper, under Rice.
  2. 3.To destroy the central nervous system of (an animal, as a frog), as by passing a stout wire or needle up and down the vertebral canal.

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