means A small, oily edible seed that grows in pods underground on a legume plant, eaten roasted, salted, or ground into butter.

from Exactly what it says on the shell: a compound of 'pea' and 'nut,' coined because the seeds resemble peas while being eaten like nuts — though botanically it's neither, but a legume. The older name was 'groundnut,' a nod to its odd habit of ripening its pods beneath the soil. 'Pea' descends from Latin 'pisum' (by way of an old singular 'pease' that English mistook for a plural), and 'nut' comes from a long Germanic line, related to Old English 'hnutu.'