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

superfluous \super"fluous\, a. l. superfluus overflowing;
   super over, above + fluere to flow. see super-, and
   fluent.
   more than is wanted or is sufficient; rendered unnecessary by
   superabundance; unnecessary; useless; excessive; as, a
   superfluous price. --shak.
   1913 webster

         an authority which makes all further argument or
         illustration superfluous.                --e. everett.
   1913 webster

   superfluous interval mus., an interval that exceeds a
      major or perfect interval by a semitone.
      1913 webster

   syn: unnecessary; useless; exuberant; excessive; redundant;
        needless.
        1913 webster -- super"fluously, adv. --
        super"fluousness, n.
        1913 webster
see also:
super- fluent superfluous interval super"fluously super"fluousness 

[2] : WordNet (r) 2.0

superfluous
     adj 1: serving no useful purpose; having no excuse for being;
            "otiose lines in a play"; "advice is wasted words"
            syn: otiose, pointless, wasted
     2: more than is needed, desired, or required; "trying to lose
        excess weight"; "found some extra change lying on the
        dresser"; "yet another book on heraldry might be thought
        redundant"; "skills made redundant by technological
        advance"; "sleeping in the spare room"; "supernumerary
        ornamentation"; "it was supererogatory of her to gloat";
        "delete superfluous or unnecessary words"; "extra ribs
        as well as other supernumerary internal parts"; "surplus
        cheese distributed to the needy" syn: excess, extra,
        redundant, spare, supererogatory, supernumerary, surplus
see also:
otiose pointless wasted excess extra redundant 
spare supererogatory supernumerary surplus 

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

73 moby thesaurus words for "superfluous":
   accessory, accidental, additional, adscititious, adventitious,
   aimless, appurtenant, ascititious, auxiliary, casual,
   circumstantial, collateral, contingent, de trop, dispensable,
   excess, excessive, expendable, expletive, extra, feckless,
   fortuitous, gratuitous, impotent, in excess, incidental,
   ineffective, ineffectual, inessential, left, leftover, meaningless,
   needless, net, no go, nonessential, odd, of no use, outstanding,
   over, pleonastic, pointless, prolix, purposeless, redundant,
   remaining, remanent, secondary, spare, subsidiary, superabundant,
   superadded, supererogatory, supernumerary, supervenient,
   supplemental, supplementary, surplus, surviving, tautologic,
   tautologous, to spare, unasked, unavailing, uncalled-for,
   unconsumed, unessential, unnecessary, unneeded, unused, unwanted,
   useless, verbose

Superfluous >> S Words
Superfluous, definition of term: Superfluous
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