The Collaborative International Dictionary of English v.0.48:

Incomparable \In*com"pa*ra*ble\, a. [L. incomparabilis: cf. F.
   incomparable. See In- not, and Comparable.]
   Not comparable; admitting of no comparison with others;
   unapproachably eminent; without a peer or equal; matchless;
   peerless; transcendent.
   [1913 Webster]

         A merchant of incomparable wealth.       --Shak.
   [1913 Webster]

         A new hypothesis . . . which hath the incomparable Sir
         Isaac Newton for a patron.               --Bp.
                                                  Warburton.
   -- In*com"pa*ra*ble*ness, n. -- In*com"pa*ra*bly, adv.
   [1913 Webster]

         Delights incomparably all those corporeal things. --Bp.
                                                  Wilkins.
   [1913 Webster]

WordNet (r) 3.0 (2006):

incomparable
    adj 1: such that comparison is impossible; unsuitable for
           comparison or lacking features that can be compared; "an
           incomparable week of rest and pleasure"; "the computer
           proceeds with its incomparable logic and efficiency";
           "this report is incomparable with the earlier ones
           because of different breakdowns of the data" [syn:
           incomparable, uncomparable] [ant: comparable]

Moby Thesaurus II by Grady Ward, 1.0:

69 Moby Thesaurus words for "incomparable":
   alien, apart, beyond compare, beyond comparison, detached,
   disconnected, discrete, disjunct, disrelated, dissimilar,
   dissociated, easily first, exotic, extraneous, facile princeps,
   foreign, immortal, incommensurable, incommensurate, independent,
   inimitable, insular, invincible, irrelative, isolated, matchless,
   nonpareil, not comparable to, nulli secundus, of different orders,
   other, outlandish, peerless, removed, second to none, segregate,
   separate, separated, strange, sui generis, superior, superlative,
   supreme, surpassing, transcendent, unaffiliated, unallied,
   unapproachable, unapproached, unassociated, unbeatable,
   unconnected, unequaled, unexampled, unexcelled, unique, unlike,
   unmatchable, unmatched, unparagoned, unparalleled, unpeered,
   unrelatable, unrelated, unrivaled, unsurpassable, unsurpassed,
   without equal, without parallel



The Free On-line Dictionary of Computing (30 December 2018):

incomparable

    Two elements a, b of a set are incomparable
   under some relation <= if neither a <= b, nor b <= a.

   (1995-09-21)