'incomparability' originates from Latin, specifically from the adjective 'incomparabilis' and the verb root 'comparare', where the prefix 'in-' meant 'not' and the root 'par/pares' meant 'equal' (related to 'par' = 'equal').

'incomparabilis' in Late Latin passed into Old French and Middle English as 'incomparable' (adjective), and the noun-forming suffix '-ity' was added in English to form 'incomparability'.

Initially it meant 'not able to be compared' (i.e. not comparable); over time it came to be used to express 'being beyond comparison' or 'supreme/unmatched quality'.