'manuscriptological' is built from 'manuscript' + the combining form '-ology' + the adjective suffix '-ical'. 'manuscript' ultimately comes from Latin 'manu scriptus', where 'manu' meant 'hand' and 'scriptus' meant 'written'.

'manuscript' came into English via Old French 'manuscrit' from Latin 'manu scriptus'; the modern academic formation 'manuscriptology' and its adjective 'manuscriptological' are later scholarly coinages using the productive English/Greek '-ology' + '-ical' pattern.

Initially the Latin phrase meant 'hand-written'; over time the compound formations came to mean 'pertaining to the study or analysis of manuscripts', which is the current specialized sense.