pocket-size

The compound "pocket-size" is a modern English formation, directly combining two native lexical items. "Pocket" entered English from the Anglo-Norman dialect of Old French, where it was a diminutive for a bag or pouch. "Size" has a more complex journey, originating from the Latin verb assidere ("to sit beside, assess"), which evolved into the Old French legal term for a fixed standard or ordinance. By the 14th century, "size" in English generalized to mean dimensions or magnitude. The logic of the compound is transparently descriptive: an object whose dimensions are such that it fits into a pocket, with the term now used figuratively to describe anything very small or conveniently compact.

Structure: pocket (noun) + size (noun) - pocket: Origin: Middle English, from Anglo-Norman poket, a diminutive form. Functional role: The first element, acting as a noun modifier meaning "of or for a pocket." - size: Origin: Middle English, from Old French sise, an aphetic form of assise meaning "assize, ordinance." Functional role: The second element, a noun meaning "dimensions, magnitude."