flavor (n.)youdaoicibaDictYouDict[flavor 词源字典]
c. 1300, "a smell, odor" (usually a pleasing one), from Old French flaor "smell, odor; action of smelling, sense of smell," probably from Vulgar Latin flator "odor," literally "that which blows," in classical Latin "blower," from flare "to blow, puff," which is cognate with Old English blawan (see blow (v.1)).

"Not common before Milton's time" [Century Dictionary], and it is not clear what exactly Milton meant when he used it. The same Vulgar Latin source produced Old Italian fiatore "a bad odor." Sense of "taste, savor" is 1690s, perhaps 1670s; originally "the element in taste which depends on the sense of smell." The -v- in the English word is euphonic or perhaps from influence of savor. Flavor-of-the-month is from 1946 (originally of ice cream).[flavor etymology, flavor origin, 英语词源]
flavor (v.)youdaoicibaDictYouDict
1540s, "communicate a distinctive quality to," from flavor (n.). Meaning "add a flavoring substance to" is from 1740. Earliest use was now-obsolete sense of "to smell" (early 15c.). Related: Flavored; flavoring.