neb·u·lous 
/ˈnɛbjələs/ adjective
/ˈnɛbjələs/ adjective formal : not clear : difficult to see, understand, describe, etc.
▪ These philosophical concepts can be nebulous. ▪ She gave a nebulous [=vague] answer to the question.
▪ These philosophical concepts can be nebulous. ▪ She gave a nebulous [=vague] answer to the question.
