pea /ˈpiː/ noun
plural peas
plural peas
Learner's definition of PEA
: a small, round, green seed that is eaten as a vegetable and that is formed in a seed case (called a pod) of a climbing plant
also : a plant that produces peas
see color picture on this page; see also black-eyed pea, chickpea, snap pea, snow pea, sugar snap pea, sweet pea

two peas in a pod

used to say that two people or things are very similar to each other