capable of being reached only with great difficulty or not at all
not capable of being obtained; "a rare work, today almost inaccessible"; "timber is virtually unobtainable in the islands"; "untouchable resources buried deep within the earth"
an obstruction that stands in the way (and must be removed or surmounted or circumvented)
something immaterial that stands in the way and must be circumvented or surmounted; "lack of imagination is an obstacle to one's advancement"; "the poverty of a district is an obstacle to good education"; "the filibuster was a major obstruction to the success of their plan"
not prudent or wise; "very imprudent of her mother to encourage her in such silly romantic ideas"; "would be imprudent for a noneconomist to talk about the details of economic policy"- A.M.Schlesinger
including all or everything; "comprehensive coverage"; "a comprehensive history of the revolution"; "a comprehensive survey"; "a comprehensive education"
broad in scope; "a comprehensive survey of world affairs"