Synonyms for Ungraded (same or very similar meaning)
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
From the ODE community, based on WordNet
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