Unpriced comes from un- ('not') + priced, from price, from Old French pris, from Latin pretium ('price, value, reward'). In current use it is an adjective meaning "having no price marked or assigned". That sense is explained by the older material without requiring a speculative semantic step: the inherited or borrowed base supplies the field of meaning, while the English formation fixes its modern role. The prefix un- is negative or privative, marking the absence, denial, or opposite of the base idea. The surface form is compositional: its joined elements remain visible in the modern word. The historical chain includes Old English un- and Latin pretium. Related English forms include price, priced, and unprice. As a result, the modern word is best read as a negative, privative, or reversative formation built on a historically older base.