The word 'vary' entered English in the 14th century from Old French varier, which itself originated from Latin variare ("to make diverse, change, alter"). The Latin verb is derived from the adjective varius, meaning "diverse, spotted, variegated," a term whose own origins are uncertain but may relate to the concept of mixture or difference. The core semantic thread from the literal "spotted" or "multicolored" to the abstract "to change" follows a common metaphorical path where visual diversity represents changeability. The modern English verb retains this fundamental sense of introducing or exhibiting difference and divergence from a standard or norm.

Structure: var (diverse) + y (verb suffix) var (from Latin varius, meaning "diverse, varied, spotted"). y (a verb-forming suffix in English, often from Old English -ian or French -ier).