Use the adjective nebulous for situations that are "hazy, indistinct" and also "cloudy" or "fuzzy."
Nebulous comes from its Latin relative nebulosus and they mean "fuzzy," "hazy," and "without distinct outlines." They both come from the noun form, nebula, which is a "mist" or "fog." In astronomy, a nebula is a fuzzy cloud of gaseous matter and something nebulous is made up of such ingredients hydrogen and galactic dust.