'unalloyed' originates from the prefix 'un-' meaning 'not' and the word 'alloyed,' which comes from the Old French 'aloier,' meaning 'to combine or mix.'

'alloyed' transformed from the Old French word 'aloier' and eventually became the modern English word 'alloyed,' with 'unalloyed' forming by adding the prefix 'un-' to denote the absence of mixing.

Initially, 'alloyed' meant 'to combine or mix metals,' but 'unalloyed' evolved to mean 'pure or not mixed with other substances.'