'unlabored' originates from English, specifically the prefix 'un-' + the past participle 'labored', where 'un-' meant 'not' and 'labor' meant 'toil' or 'work'.

'labored' derives from Middle English 'labour' (from Old French 'labour'), ultimately from Latin 'labor, laboris' meaning 'toil, work'. The negative prefix 'un-' comes from Old English 'un-' meaning 'not'. These elements combined in modern English to form 'unlabored'.

Initially it meant 'not produced by toil' or simply 'not laborious' (literal absence of labor); over time it broadened to describe style, manner, or action that appears effortless or unforced.