ETYM as. pitha; akin to Dutch pit pith, kernel, lg. peddik. Related to Pit a kernel.
1. A usually continuous central strand of spongy tissue in the stems of most vascular plants that probably functions chiefly in storage.
2. Soft spongelike central cylinder of the stems of most flowering plants.
3. The soft or spongy interior of a part of the body.
4. The essential part; core; substantial quality (as of meaning).
5. Importance.

1. To kill (as cattle) by piercing or severing the spinal cord; to destroy the spinal cord or central nervous system of (as a frog) usually by passing a wire or needle up and down the vertebral canal
2. To remove the pith from (a plant stem)