'Questionable' definitions:

Definition of 'questionable'

From: WordNet
adjective
Subject to question; "questionable motives"; "a questionable reputation"; "a fire of questionable origin" [ant: unquestionable]
adjective
Able to be refuted [syn: questionable, refutable, confutable, confutative]

Definition of 'Questionable'

From: GCIDE
  • Questionable \Ques"tion*a*ble\, a.
  • 1. Admitting of being questioned; inviting, or seeming to invite, inquiry. [R.] [1913 Webster]
  • Thou com'st in such a questionable shape That I will speak to thee. -- Shak. [1913 Webster]
  • 2. Liable to question; subject to be doubted or called in question; problematical; doubtful; suspicious. [1913 Webster]
  • It is questionable whether Galen ever saw the dissection of a human body.T. -- Baker. [1913 Webster]
  • Syn: Disputable; debatable; uncertain; doubtful; problematical; suspicious. [1913 Webster]

Synonyms of 'questionable'

From: Moby Thesaurus