(stā′pəl) noun
1. A principal commodity or production of a country or region; a well–established article of commerce.
2. A chief element or main constituent of something.
3. The carded or combed fiber of cotton, wool, or flax.
4. Raw material.
5. A commercial emporium; mart.
6. Hence, a source of supply; storehouse.
—adjective
1. Regularly and constantly produced or sold; hence, main; chief.
2. Commercially established; having regular commercial channels.
3. Marketable.
—v.t. ·pled, ·pling To sort or classify according to length, as wool fiber. [<OF estaple market, support <Gmc.]

(stā′pəl) noun
A U–shaped piece of metal with pointed ends, or a loop of thin wire, driven into wood, fabrics, paper, etc., to serve as a fastening.
—v.t. ·pled, ·pling To fix or fasten by a staple or staples. [OE stapol post, prop]