problematical in WordNet English dictionary

1. making great mental demands; hard to comprehend or solve or believe
   "a baffling problem"; "I faced the knotty problem of what to have for breakfast"; "a problematic situation at home"
   baffling  elusive  knotty  problematic  problematical  tough 
   
2. open to doubt or debate
   "If you ever get married, which seems to be extremely problematic"
   debatable  problematic  problematical