'one-syllabled' originates from Modern English, formed by combining 'one' (from Old English 'ān') with 'syllabled', which derives from 'syllable' (from Latin 'syllaba' and Greek 'syllabē'); the adjective sense is produced by the suffix '-ed'.

'one' comes from Old English 'ān', while 'syllable' entered English via Latin 'syllaba' (from Greek 'syllabē'); the adjective 'syllabled' developed by adding the adjectival suffix '-ed' and was compounded with 'one' to form 'one-syllabled'.

Initially the roots referred simply to the numeral 'one' and the unit of sound 'syllable'; combined as 'one-syllabled' they have long meant 'consisting of a single syllable', a meaning that has remained stable.