Pea (pisum in Latin) is a pulse, vegetable or fodder crop, but the word often refers to the seed or sometimes the pod of this flowering plant species. Carl Linnaeus gave the species the scientific name Pisum sativum in 1753 (meaning cultivated pea). Some sources now treat it as Lathyrus oleraceus; however the need and justification for the change is disputed. Each pod contains several seeds (peas), which can have green or yellow cotyledons when mature. Botanically, pea pods are fruit, since they contain seeds and develop from the ovary of a (pea) flower. The name is also used to describe other edible seeds from the Fabaceae such as the pigeon pea (Cajanus cajan), the cowpea (Vigna unguiculata), the seeds from several species of Lathyrus and is used as a compound form for example Sturt's desert pea.

Peas are annual plants, with a life cycle of one year. They are a cool-season crop grown in many parts of the world; planting can take place from winter to early summer depending on location. The average pea weighs between 0.1 and 0.36 gram. The immature peas (and in snow peas the tender pod as well) are used as a vegetable, fresh, frozen or canned; varieties of the species typically called field peas are grown to produce dry peas like the split pea shelled from a matured pod. These are the basis of pease porridge and pea soup, staples of medieval cuisine; in Europe, consuming fresh immature green peas was an innovation of early modern cuisine.