macaroni: [16] Macaroni was the earliest of the Italian pasta terms to be borrowed into English, and so it now differs more than any other from its original. When English acquired it, the Italian word was maccaroni (it came ultimately from late Greek makaría ‘food made from barley’), but now it has become maccheroni. The colloquial 18th-century application of macaroni to a ‘dandy’ is thought to have been an allusion to such people’s supposed liking for foreign food.
And the derivative macaronic [17], used for a sort of verse in which Latin words are mixed in with vernacular ones for comic effect, was originally coined in Italian, comparing the verse’s crude mixture of languages with the homely hotchpotch of a macaroni dish. Macaroon [17] comes from macaron, the French descendant of Italian maccaroni. => macaroon
macaroni (n.)
"tube-shaped food made of dried wheaten paste" [Klein], 1590s, from southern Italian dialectal maccaroni (Italian maccheroni), plural of maccarone, name for a kind of pasty food, possibly from maccare "bruise, batter, crush," which is of unknown origin, or from late Greek makaria "food made from barley."
Used by 1769 to mean "a fop, a dandy" ("typical of elegant young men" would be the sense in "Yankee Doodle") because it was an exotic dish at a time when certain young men who had traveled the continent were affecting French and Italian fashions and accents. There is said to have been a Macaroni Club in Britain, which was the immediate source of this usage in English.