Synonyms for Retrograde (same or very similar meaning)
WordNet sense 1 (move back):
retreat
WordNet sense 2 (going from better to worse):
retrogressive
WordNet sense 3 (opposing progress; returning to a former less advanced state):
regressive
WordNet sense 4 (go back over):
rehash, rehash, hash over
WordNet sense 5 (get worse or fall back to a previous condition):
regress, retrogress, regress
WordNet sense 6 (moving or directed or tending in a backward direction or contrary to a previous direction):
retral
WordNet sense 7 (directed or facing toward the back or rear):
backward
From the ODE community, based on WordNet
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