The compound adjective 'three-hundred-pound' is a modern English construction built from three distinct numerical and measurement roots. 'Three' and 'hundred' both trace back to ancient Indo-European counting systems, with 'hundred' evolving from a base meaning 'ten' to signify a specific large count. 'Pound' entered English via Germanic languages from the Latin term for a specific weight unit. The compound's logic is purely descriptive and arithmetic, combining these established elements to specify a precise weight of 300 units in the avoirdupois system, showcasing English's analytical capacity for creating clear, compound modifiers.

Structure: three (3) + hundred (100) + pound (unit of weight) - three: From Old English þrīe, þrēo, of Germanic origin; related to Dutch drie and German drei, from an Indo-European root shared by Latin tres and Greek treis. Functions as a cardinal number. - hundred: From Old English hund, of Germanic origin; related to Dutch honderd and German hundert. The ultimate origin is from an Indo-European root meaning 'ten', which also gave rise to Latin centum and Greek hekaton. Functions as a numeral multiplier. - pound: From Old English pund, of Germanic origin; related to Dutch pond and German Pfund, from Latin (libra) pondo, denoting a Roman pound weight. Functions as a unit of measurement.