Wordnet 3.0
NOUN (2)
1. 
 a British dandy in the 18th century who affected Continental mannerisms; 
- Example: "Yankee Doodle stuck a feather in his cap and called it macaroni"2. 
 pasta in the form of slender tubes; 
The Collaborative International Dictionary of English v.0.48:
Macaroni \Mac`a*ro"ni\, n.; pl. Macaronis, or Macaronies.
   [Prov. It. macaroni, It. maccheroni, fr. Gr. ? happiness,
   later, a funeral feast, fr. ? blessed, happy. Prob. so called
   because eaten at such feasts in honor of the dead; cf. Gr. ?
   blessed, i. e., dead. Cf. Macaroon.]
   1. Long slender tubes made of a paste chiefly of a wheat
      flour such as semolina, and used as an article of food; a
      form of Italian pasta.
      [1913 Webster]
   Note: A paste similarly prepared is largely used as food in
         Persia, India, and China, but is not commonly made
         tubular like the Italian macaroni. --Balfour (Cyc. of
         India).
         [1913 Webster]
   2. A medley; something droll or extravagant.
      [1913 Webster]
   3. A sort of droll or fool. [Obs.] --Addison.
      [1913 Webster]
   4. A finical person; a fop; -- applied especially to English
      fops of about 1775, who affected the mannerisms and
      clothing of continental Europe. --Goldsmith.
      [1913 Webster]
   5. pl. (U. S. Hist.) The designation of a body of Maryland
      soldiers in the Revolutionary War, distinguished by a rich
      uniform. --W. Irving.
      [1913 Webster] Macaronian
WordNet (r) 3.0 (2006):
macaroni
    n 1: a British dandy in the 18th century who affected
         Continental mannerisms; "Yankee Doodle stuck a feather in
         his cap and called it macaroni"
    2: pasta in the form of slender tubes
Moby Thesaurus II by Grady Ward, 1.0:
43 Moby Thesaurus words for "macaroni":
   Beau Brummel, Italian paste, beau, blade, blood, boulevardier,
   buck, clotheshorse, coxcomb, dandy, dude, dumpling, exquisite,
   fashion plate, fedellini, fettuccine, fine gentleman, fop, fribble,
   gallant, jack-a-dandy, jackanapes, knaydlach, lady-killer, lasagne,
   lounge lizard, man-about-town, masher, matzo balls, noodles, pasta,
   paste, puppy, ravioli, spaetzle, spaghetti, spaghettini, spark,
   sport, swell, vermicelli, won ton, ziti