ambrosia (n.) Look up ambrosia at Dictionary.com
1560s, "favored food or drink of the gods," from Latin ambrosia, from Greek ambrosia "food of the gods," noun use of fem. of ambrosios, probably literally "of the immortals," from ambrotos "immortal, imperishable," from a- "not" (see a- (3)) + mbrotos, related to mortos "mortal," from PIE *mer- (2) "to rub away, harm" (see mortal (adj.)). Applied to certain herbs by Pliny and Dioscorides; used of various foods for mortals since 1680s (originally of fruit drinks); used figuratively for "anything delightful" by 1731.