'disyllabic' originates from Modern Latin, specifically the word 'disyllabicus', ultimately from Greek 'disyllabos', where 'di-' meant 'two' and 'syllabē' meant 'a syllable'.

'disyllabic' changed from the Greek word 'disyllabos' to the Latin 'disyllabicus' and entered English as 'disyllabic' via Modern/New Latin.

Initially it meant 'having two syllables', and this meaning has been retained in modern English.