'unrhyming' originates from English, specifically formed from the prefix 'un-' and the word 'rhyme', where 'un-' meant 'not' and 'rhyme' meant 'rhyme or rhythmic correspondence'.

'unrhyming' developed by combining the negative prefix 'un-' (from Old English) with Middle English 'rime' (from Old French 'rime'), which through Latin and Greek roots ('rhythmus', 'rhythmos') evolved into the modern English word 'rhyme', and thus into the compound 'unrhyming'.

Initially it carried the straightforward sense of 'not forming a rhyme', and over time it has retained that basic meaning of 'lacking rhyme'.