the cultivation of plants by placing the roots in liquid nutrient solutions rather than in soil; soilless growth of plants. Compare aeroculture, geoponics(def. 2).
1937, formed in Eng. from hydro-, comb. form of Gk. hydor "water" (see water (n.1)) + -ponics, from Gk. ponein "to labor, toil," from ponos "labor" (see span (v.)).