The word 'unpaired' is a modern English formation built upon the core noun 'pair,' which entered Middle English from Old French paire, itself derived from Latin paria, the neuter plural of par meaning "equal." The Latin root traces back to the Proto-Indo-European root per-, conveying notions of granting, allotting, or bringing forth, which underlies the concept of things being matched or made equal. The prefix 'un-', of ancient Germanic lineage, is attached to negate the root, while the adjectival suffix '-ed' is added to indicate the state or quality of being not matched. Thus, the literal construction "not placed in a state of being equal/matched" logically yields the modern meaning of something existing singly without a corresponding counterpart.

Structure: un (not) + pair (two of a kind) + ed (adjective suffix) - un: A prefix of Germanic origin (Old English un-), meaning "not." It is a common negating prefix in English. - pair: A root of Latin origin (from Latin paria, "equals," from par, "equal"). It refers to two corresponding or matching items. - ed: A suffix of Germanic origin (Old English -ed, -od), commonly used to form past participles and adjectives from nouns or verbs, indicating a state or condition.