[1] : WordNet (r) 2.0

unbeatable
     adj 1: hard to defeat; "an unbeatable ball team"
     2: incapable of being overcome or subdued; "an invincible
        army"; "her invincible spirit" syn: invincible, unvanquishable
see also:
invincible unvanquishable 

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

50 moby thesaurus words for "unbeatable":
   beyond compare, beyond comparison, easily first, excellent,
   facile princeps, immortal, impenetrable, impregnable, incomparable,
   incontestable, indomitable, inexpugnable, inimitable, insuperable,
   invincible, inviolable, invulnerable, irresistible, matchless,
   nulli secundus, overpowering, overwhelming, peerless, resistless,
   second to none, sui generis, superlative, supreme, unapproachable,
   unapproached, unassailable, unconquerable, undefeatable, unequaled,
   unexampled, unexcelled, unique, unmatchable, unmatched,
   unparagoned, unparalleled, unpeered, unrivaled, unsubduable,
   unsurmountable, unsurpassable, unsurpassed, unyielding,
   without equal, without parallel

Unbeatable >> U Words
Unbeatable, definition of term: Unbeatable
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