The ordinal form of the number pi.
The essential or vital part; force; energy; importance.
The spinal cord; the marrow.
The soft, spongy substance in the center of the stems of many plants and trees.
The albedo of a citrus fruit.
The spongy interior substance of a feather or horn.
One divided by pi.
Power, strength, might.
To extract the pith from (a plant stem or tree).
To kill (especially cattle or laboratory animals) by cutting or piercing the spinal cord.