The word 'unoriginal' is a modern English formation built upon the adjective 'original'. The core concept of 'original' traces back to the Latin noun 'orīgō', meaning 'beginning' or 'source', which itself is derived from the verb 'orīrī', 'to rise'. The prefix 'un-', with its ancient Germanic roots as a negator, is one of the most productive and enduring in the English language. When combined, the morphemes create a transparent logical meaning: 'not pertaining to the source', which semantically evolved into the modern sense of lacking novelty or being derivative. This construction exemplifies how English readily employs native prefixes to modify Latinate base words to express precise, often evaluative, concepts.

Structure: un (not) + original (first or earliest) - un: A prefix of Germanic origin (Old English 'un-'), used to form adjectives and their derivatives, expressing negation or absence of a quality. - original: An adjective of Latin origin (from 'originālis'), meaning 'pertaining to the source or beginning'. It is itself derived from 'orīgō' (beginning, source).