pea-size

The compound adjective "pea-size" is a modern English formation that employs a straightforward metaphorical comparison. The first element, "pea", refers to the common green seed known for its small, round shape, a term with ancient roots tracing back to Greek pison. The second element, "size", denotes physical dimensions, a word that evolved from legal and procedural terms in Old French and Latin relating to settling or fixing an amount. When combined, the term literally means "having the dimensions of a pea," creating a vivid and universally understood benchmark for describing something very small. This logic of using a familiar, concrete object to quantify an abstract quality like scale is a common and effective feature of English compounding.

Structure: pea (seed) + size (dimension) - pea: From English "pea", a type of small, round seed. Ultimately from Latin pisum, from Greek pison. - size: From English "size", meaning the dimensions or magnitude of something. From Old French sise, from assise ("session, regulation"), from Latin assidere ("to sit beside").