Synonyms for Without basis:

• adj.

  •illogical (adjective)
  • untenable,
  • groundless,
  • inconclusive.

• Other synonyms:

  •Other relevant words:
  • undemonstrated,
  • unconfirmed,
  • unsupportable,
  • unestablished,
  • ill-founded,
  • unsupported,
  • idle,
  • baseless,
  • unauthenticated,
  • ungrounded,
  • unfixed,
  • unsustainable,
  • unwarranted,
  • unsettled,
  • uncertified,
  • indecisive,
  • empty,
  • unsubstantiated,
  • unverified,
  • undetermined,
  • vain,
  • Unsustained,
  • untested,
  • untried,
  • uncorroborated.

Antonyms for Without basis:

• adj.

  • illogical
    wise, sensible, rational, true, reasonable, right, correct, logical, meaningful.
  • unfounded
    justified, called-for, proven, genuine, honest, warranted, founded, truthful, substantiated, real, supported.