'syphilitic' originates from New Latin 'syphiliticus', formed from 'syphilis' (the name of the disease), which itself was coined in the 16th century (from a literary name 'Syphilus' used by the Italian poet Girolamo Fracastoro).

'syphiliticus' (New Latin) yielded English 'syphilitic' via Late Latin and French medical usage; the underlying disease name 'syphilis' was established in Renaissance medical and literary texts and carried into modern European languages before English adoption.

Initially used in medical and literary contexts specifically to denote the disease or its sufferers; it has remained focused on the same medical sense, though as medical terminology evolved, usage shifted toward more clinical or precise descriptions (e.g., 'syphilitic arthritis', 'neurosyphilis').