“disease,” “suffering,” “disorder” — Noun-forming compound suffix — “disease of (a named structure or system)”
The word entered English in the 1640s as pathos (noun), borrowed from French pathos, from Late Latin pathos, from Greek πάθος (pathos) — literally “suffering” or “experience.” The medical suffix form -pathy appeared in the 1860s (e.g., neuropathy). The root pathos (“suffering, disease”) connects -pathy to the entire disease and pathology suffixes: neuropathy (neuro- + pathy → disease of the nerves), myopathy (myo- + pathy → disease of muscle), and cardiomyopathy (cardio- + myo- + pathy → disease of the heart muscle). The compound suffix-pathy is extremely productive across nearly all medical specialties: e.g., osteopathy, nephropathy, hepatopathy, neurotoxicopathy, and psychopathy.