problematic + -al
problematical (comparative more problematical, superlative most problematical)
- doubtful or disputed
- dubious or ambiguous
- 1924, Herman Melville, Billy Budd, London: Constable & Co., Chapter 8, 
- The salt seer attentively listened, accompanying the Foretopman's recital with queer twitchings of his wrinkles and problematical little sparkles of his small ferret eyes.