Adjective

obscure, dark, vague, enigmatic, cryptic, ambiguous, equivocal mean not clearly understandable. obscure implies a hiding or veiling of meaning through some inadequacy of expression or withholding of full knowledge.
//obscure poems dark implies an imperfect or clouded revelation often with ominous or sinister suggestion.
// muttered dark hints of revenge vague implies a lack of clear formulation due to inadequate conception or consideration.
// a vague sense of obligation enigmatic stresses a puzzling, mystifying quality.
//enigmatic occult writings cryptic implies a purposely concealed meaning.
//cryptic hints of hidden treasure ambiguous applies to language capable of more than one interpretation.
// an ambiguous directive equivocal applies to language left open to differing interpretations with the intention of deceiving or evading.
// moral precepts with equivocal phrasing