In Greek mythology, nectar and ambrosia are the food of the gods. It is believed that the two terms were not originally distinguished—though in Homer's poems and later works, nectar is the drink and ambrosia the food. On the other hand, in Alcman nectar is the food, and in Sappho and Anaxandrides ambrosia the drink. Each is used in Homer as an unguent (Iliad, xiv. 170; xix. 38). Both are fragrant, and maybe used as perfume. According to W. H. Röscher (Nektar und Ambrosia, 1883; see also his article in Röscher's Lexikon der Mythologie) nectar and ambrosia were originally only different forms of the same substance - honey, regarded as a dew, like manna, fallen from heaven, which was used both as food and drink. See also Ichor.
In botany, nectar is a sugar-rich liquid produced by the flowers of plants in order to attract pollenating animals. Nectar is the principal raw ingredient for honey.