" incontestable "

1: not capable of being challenged or proved wrong;

  * e.g., " ... the incontestable statement that every contest has a winner and a loser "

•  Synonyms : 

•  accomplished,

•  certain,

•  inarguable,

•  incontrovertible,

•  indisputable,

•  indubitable,

•  irrefragable,

•  irrefutable,

•  positive,

•  sure,

•  unanswerable,

•  unarguable,

•  unchallengeable,

•  undeniable,

•  unquestionable

•  Antonyms : 

•  answerable,

•  arguable,

•  contradictable,

•  controvertible,

•  debatable,

•  disputable,

•  doubtable,

•  moot,

•  negotiable,

•  problematic,

•  questionable,

•  refutable