Open English Wordnet
Nouns
(n)basic, staple(usually in the plural) a necessary commodity for which demand is constant (n)staple, staple fiber, staple fibrea natural fiber (raw cotton, wool, hemp, flax) that can be twisted to form yarn“staple fibers vary widely in length” (n)staplea short U-shaped wire nail (n)staplepaper fastener consisting of a short length of U-shaped wire that can fasten papers together Verbs
(v)staplesecure or fasten with a staple or staples“staple the papers together” Adjectives
(s)staplenecessary or important, especially regarding food or commodities“wheat is a staple crop”