An Etymological Dictionary of the German Language/Annotated/gesund
gesund, adjective, ‘sound, healthy, wholesome,’ from the equivalent Middle High German gesunt(d), Old High German gisunt(t); also Middle High German gesunt, Old High German gisunt, m, ‘health’; compare Anglo-Saxon gesund and sund, English sound, Dutch gezond, Old Frisian sund. To East Teutonic the word is unknown. Its connection with Latin sânus, ‘healthy,’ is as feasible phonetically as its connection with geschwind, or with the Teutonic root sinþ, ‘to go,’ in Gesinde.