From WordNet (r) 3.0 (2006):
staple
adj 1: necessary or important, especially regarding food or
commodities; "wheat is a staple crop"
n 1: (usually plural) a necessary commodity for which demand is
constant [syn: basic, staple]
2: a natural fiber (raw cotton, wool, hemp, flax) that can be
twisted to form yarn; "staple fibers vary widely in length"
[syn: staple, staple fiber, staple fibre]
3: material suitable for manufacture or use or finishing [syn:
raw material, staple]
4: a short U-shaped wire nail for securing cables
5: paper fastener consisting of a short length of U-shaped wire
that can fasten papers together
v 1: secure or fasten with a staple or staples; "staple the
papers together" [ant: unstaple]