[1] : The Collaborative International Dictionary of English v.0.48

illustrious \illus"trious\, a. l. illustris, prob. for
   illuxtris; fr. il- in + the root of lucidus bright: cf. f.
   illustre. see lucid.
   1. possessing luster or brightness; brilliant; luminous;
      splendid.
      1913 webster

            quench the light; thine eyes are guides illustrious.
                                                  --beau.  fl.
      1913 webster

   2. characterized by greatness, nobleness, etc.; eminent;
      conspicuous; distinguished.
      1913 webster

            illustrious earls, renowened everywhere. --drayton.
      1913 webster

   3. conferring luster or honor; renowned; as, illustrious
      deeds or titles.

   syn: distinguished; famous; remarkable; brilliant;
        conspicuous; noted; celebrated; signal; renowened;
        eminent; exalted; noble; glorious. see distinguished,
        famous.
        1913 webster
see also:
lucid distinguished famous 

[2] : WordNet (r) 2.0

illustrious
     adj 1: widely known and esteemed; "a famous actor"; "a celebrated
            musician"; "a famed scientist"; "an illustrious
            judge"; "a notable historian"; "a renowned painter"
            syn: celebrated, famed, far-famed, famous, notable,
             noted, renowned
     2: having or conferring glory; "an illustrious achievement"
     3: having or worthy of pride; "redoubtable scholar of the
        renaissance"; "born of a redoubtable family" syn: glorious,
         redoubtable, respected
see also:
celebrated famed far-famed famous notable noted 
renowned glorious redoubtable respected 

[3] : Moby Thesaurus II by Grady Ward, 1.0

38 moby thesaurus words for "illustrious":
   acclaimed, bright, brilliant, celebrated, charismatic, conspicuous,
   distinguished, eminent, esteemed, famed, famous, glamorous,
   glorious, great, honored, important, lofty, lustrous, magic,
   notable, noted, numinous, outstanding, prominent, radiant,
   renowned, respected, resplendent, shining, signal, splendent,
   splendid, splendorous, splendrous, striking, sublime, venerable,
   well-known

[4] : THE DEVIL'S DICTIONARY ((C)1911 Released April 15 1993)

illustrious, adj.  suitably placed for the shafts of malice, envy and
detraction.

Illustrious >> I Words
Illustrious, definition of term: Illustrious
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