staple (2) /ˈsteɪpl / ▸ noun 1 a main or important element of something: bread, milk, and other staples
Greek legend was the staple of classical tragedy.
▪ a main item of trade or production: rubber became the staple of the Malayan economy.2 [mass noun] the fibre of cotton or wool considered with regard to its length and degree of fineness: [in combination] jackets made from long-staple Egyptian cotton [as modifier] he tested the lint for staple length and strength.
3 [often with modifier] historical a centre of trade, especially in a specified commodity: proposals were made for a wool staple at Pisa.
▸ adjective [attributive] main or important, especially in terms of consumption: the staple foods of the poor
violence is the staple diet of the video generation figurative.▪ most important in terms of trade or production: rice was the staple crop grown in most villages.