n. - The soft spongy substance in the center of the stems of many plants and trees, especially those of the dicotyledonous or exogenous classes. It consists of cellular tissue.
n. - The spongy interior substance of a feather.
n. - The spinal cord; the marrow.
n. - Hence: The which contains the strength of life; the vital or essential part; concentrated force; vigor; strength; importance; as, the speech lacked pith.
v. t. - 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.