Emily Dickinson Lexicon

PEA, n. [Sax. pisa; Fr. pois; It. pisello; L. pisum; Gr. πισον; W. pys, pysen; Ir. pis.]

A plant and its fruit of the genus Pisum of many varieties. This plant has a papilionaceous flower, and the pericarp of a legume, called in popular language a pod. In the plural we write peas, for two or more individual seeds, but pease for an indefinite number in quantity or bulk. We write two, three or four peas, but a bushel of pease. [This practice is arbitrary and improper.]