late 14c., saluten, "to greet courteously and respectfully," earlier salue (c. 1300, from Old French salver), from Latin salutare "to greet, pay respects," literally "wish health to," from salus (genitive salutis) "greeting, good health," which is related to salvus "safe" (from PIE root *sol- "whole, well-kept").
The military and nautical sense of "display flags, fire cannons, etc., as a mark of ceremonious recognition or respect" is recorded from 1580s; specific sense of "raise the hand to the cap in the presence of a superior officer" is from 1844. In 18c. use often "to greet with a kiss."
mid-15c., "food or medicine which restores health or strength," from restorative (adj.), or from Medieval Latin restaurativum "a restorative," noun use of the neuter of restorativus.
Jewish word of greeting, Hebrew, literally "peace," properly "completeness, soundness, welfare," from stem of shalam "was intact, was complete, was in good health." Related to Arabic salima "was safe," aslama "surrendered, submitted" (compare Islam).
1823, "pertaining to health or hygiene," from French sanitaire (1812), from Latin sanitas "health," from sanus "healthy; sane" (see sane). In reference to menstrual devices, by 1881 (in sanitary towel). In U.S. history the Sanitary Commission, created by the Secretary of War in 1861, provided relief to soldiers and oversaw military lodging and hospitals. Sanitarian is by 1859 as "promoter of, or one versed in, sanitary measures or reforms;" sanitarist in that sense also is by 1859.
1848, "practical and scientific methods of preservation of health and promotion of sanitary conditions," irregularly formed from sanitary. The somewhat euphemistic use in reference to garbage and domestic waste disposal is (as in sanitation engineer) is by 1916 (sanitation man).
c. 1300, sauf, "unscathed, unhurt, uninjured; free from danger or molestation, in safety, secure; saved spiritually, redeemed, not damned;" from Old French sauf "protected, watched-over; assured of salvation," from Latin salvus "uninjured, in good health, safe," which is related to salus "good health," saluber "healthful" (all from PIE *solwos from root *sol- "whole, well-kept"). For the phonological development of safe from sauf, OED compares gage from Old North French gauge.
From late 14c. as "rescued, delivered; protected; left alive, unkilled." The meaning "not exposed to danger" (of places, later of valuables) is attested from late 14c.; in reference to actions, etc., the meaning "free from risk," is recorded by 1580s. The sense of "sure, reliable, not a danger" is from c. 1600. The sense of "conservative, cautious" is from 1823. It has been paired alliteratively with sound (adj.) from c. 1300. In Middle English it also meant "in good health," also "delivered from sin or damnation." Related: Safeness.
1846, toast or expression wishing good health (from 16c., famously a drinking pledge by German students), Latin, literally "may it advantage (you)," third person singular present subjunctive of prodesse "to do good, be profitable" (see proud (adj.)).