WordNet sense 1 ((of roads) not leveled or drained; unsuitable for all year travel):

dirt

WordNet sense 2 (not made more desirable or valuable or profitable; especially not made ready for use or marketing):

unimproved

WordNet sense 3 (not arranged in order hierarchically):

unordered, unranked

WordNet sense 4 (not classified hierarchically):

nonhierarchic, nonhierarchical