"dried berries of the pepper plant," Middle English peper, from Old English pipor, from an early West Germanic borrowing of Latin piper "pepper," from Greek piperi, probably (via Persian) from Middle Indic pippari, from Sanskrit pippali "long pepper." The Latin word is the source of German Pfeffer, Italian pepe, French poivre, Old Church Slavonic pipru, Lithuanian pipiras, Old Irish piobhar, Welsh pybyr, etc.
Application to fruits of the Capsicum family (unrelated, originally native of tropical America) is from 16c. To have pepper in the nose in Middle English was "to be supercilious or unapproachable."
"to sprinkle as with pepper," 1610s, from pepper (n.). Old English had gepipera. Meaning "to pelt with shot, etc.; hit with what pains or annoys" is from 1640s. Related: Peppered; peppering.
Old English swete "pleasing to the senses, mind or feelings; having a pleasant disposition," from Proto-Germanic *swotja- (source also of Old Saxon swoti, Old Frisian swet, Swedish söt, Danish sød, Middle Dutch soete, Dutch zoet, Old High German swuozi, German süß), from PIE root *swād- "sweet, pleasant" (Sanskrit svadus "sweet;" Greek hedys "sweet, pleasant, agreeable," hedone "pleasure;" Latin suavis "pleasant" (not especially of taste), suadere "to advise," properly "to make something pleasant to"). Words for "sweet" in Indo-European languages typically are used for other sense as well and in general for "pleasing."
Then come kiss me, sweet-and-twenty!
Youth's a stuff will not endure.
["Twelfth Night"]
Also "being in a sound or wholesome state" (mid-13c.), and, of water, "fresh, not salt" (late Old English). As an intensifier from 1958. Sweet in bed (c. 1300) was the equivalent of modern "good in bed."
To be sweet on someone is recorded by 1690s. Sweet sixteen is recorded by 1767. Sweet dreams as a parting to one going to sleep is attested from 1897, short for sweet dreams to you, etc. Sweet-and-sour in cookery is from 1723 and not originally of Eastern dishes. Sweet nothings "sentimental trivialities" is from 1900. Sweet spot is from 1976, first in reference to tennis rackets. Sweet corn is from 1640s.
soft drink, patented 1906 by the Dr. Pepper Co., Dallas, Texas; said to have been named for U.S. physician Dr. Charles Pepper (1830-1903), medical doctor and Confederate surgeon during the Civil War.
"right away, promptly," 1917, American English, representing U.S. soldiers' mangled adaptation of French tout de suite.
Sweet-talk, 1935, from noun phrase; see sweet (adj.) + talk (n.). Earliest usages seem to refer to conversation between black and white in segregated U.S.
"I ain' gonna stay heah no longah. Don' nevah keer, ef I do git cotched—or die. Tha's bettah than to stay heah an' listen to Maw Haney sweet-talk the white folks, whilst they drives us clean to the grave. ..." [The Crisis, July 1935]
Latin had suaviloquens, literally "sweet-spoken."