pure-tone

The compound "pure-tone" is a modern technical term formed from two ancient roots to describe a specific acoustic phenomenon. "Pure" originates from the Latin purus, meaning clean or unmixed, a concept that passed into English with little semantic change. "Tone" derives from the Greek tonos, meaning tension or pitch, which entered English via Latin and Old French, broadening from musical pitch to general sound quality. The logic of the compound is transparent: it directly combines the idea of an unmixed, clean state ("pure") with that of a sound or musical note ("tone") to denote a sound wave of a single frequency, free from the harmonic complexity found in most natural sounds.

Structure: pure (clean, unmixed) + tone (sound, pitch) • pure: From Latin purus (clean, clear, unmixed). Functions as an adjective modifying the nature of the 'tone'. • tone: From Greek tonos (tension, pitch, accent) via Latin tonus. Functions as the core noun meaning a sound or musical note.