An Etymological Dictionary of the German Language/gesund
gesund, adj., ‘sound, healthy, wholesome,’ from the equiv. MidHG. gesunt(d), OHG. gisunt(t); also MidHG. gesunt, OHG. gisunt, m, ‘health’; comp. AS. gesund and sund, E. sound, Du. gezond, OFris. sund. To East Teut. the word is unknown. Its connection with Lat. sânus, ‘healthy,’ is as feasible phonetically as its connection with geschwind, or with the Teut. root sinþ, ‘to go,’ in Gesinde.