before 900; (adj. and adv.) Middle Englishswet(e), Old Englishswēte (adj.); (noun) Middle Englishswet(e), derivative of the adj.; cognate with Old Saxonswōti,Old High Germanswuozi (Germansüss); akin to Dutchzoet,Old Norsesætr,Gothicsuts,Greekhēdýs sweet, Latinsuādēre to recommend, suāvis pleasant
O.E. swete "pleasing to the senses, mind or feelings," from P.Gmc. *swotijaz (cf. O.S. swoti, Swed. söt, Dan. sød, M.Du. soete, Du. zoet, O.H.G. swuozi, Ger. süß), from PIE base *swad- (Skt. svadus "sweet;" Gk. hedys "sweet, pleasant, agreeable," hedone "pleasure;" L. suavis "sweet," suadere "to advise," prop. "to make something pleasant to"). Sweetbread "pancreas used as food" is from 1565 (the -bread element may be from O.E. bræd "flesh"). To be sweet on someone is first recorded 1694. Sweet-talk (v.) dates from 1936 (in "Gone With the Wind"). Sweet sixteen first recorded 1826. Sweet dreams as a parting to one going to sleep is attested from 1908. Sweet and sour in cooking is from 1723, not originally of oriental food.
c.1300, "something sweet to the taste," also "beloved one," from sweet (adj.); the meaning "candy drop" is 1851 (earlier sweetie, 1721).