2、pea:  Pea is the mirror-image of dice. Dice started off as the plural of die, but has become a singular form; the singular form of pea was originally pease, but it came to be regarded as plural, and so a new singular pea was created. The word was originally acquired in the Old English period from Latin pisa, which in turn got it from Greek píson. The old singular form survives in pease pudding. Relatives of the word include French pois, Italian pisello, and Welsh pysen.
4、early or mid-17c., false singular from Middle English pease (plural pesen), which was both single and collective (as with wheat, corn) but the"s"sound was mistaken for the plural inflection. From Old English pise (West Saxon), piose (Mercian)"pea,"from Late Latin pisa, variant of Latin pisum"pea,"from Greek pison"the pea,"perhaps of Thracian or Phrygian origin [Klein]. In Southern U.S. and the Caribbean, used of other legumes as well. Pea soup is first recorded 1711 (pease-soup); applied to London fogs since at least 1849. Pea-shooter attested from 1803.