Open to doubt (13)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">open to doubt</span>' is the definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for problematical that I've seen before include "Dubious" , "Open to doubt or debate" , "Presenting difficulties" , "Difficult; doubtful" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">open to doubt</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for questionable that I've seen before include "Open to doubt" , "Dubious" , "Controversial" , "Suspect, unproven" , "Doubtful - possibly dishonest" .)