kind of herb (Salvia officinalis), c.1310, from O.Fr. sauge (13c.), from L. salvia, from salvus "healthy" (see safe). So called for its healing or preserving qualities (it was used to keep teeth clean and relieve sore gums, and boiled in water to make a drink to alleviate arthritis). In Eng. folklore, sage, like parsley, is said to grow best where the wife is dominant. Sagebrush first recorded 1852.
"wise," c.1300, from O.Fr. sage (11c.), from Gallo-Romance *sabius, from V.L. *sapius, from L. sapere "have a taste, have good taste, be wise," from PIE base *sap- "to taste." The noun meaning "man of profound wisdom" is recorded from c.1300. Originally applied to the Seven Sages -- Thales, Solon, Periander, Cleobulus, Chilon, Bias, and Pittacus.