Synonyms for Unimaginative (same or very similar meaning)
WordNet sense 1 (concerned with actual use or practice):
practical
WordNet sense 2 (deficient in originality or creativity; lacking powers of invention):
sterile, uninspired, uninventive
WordNet sense 3 (lacking spontaneity or originality or individuality):
stereotyped, stereotypical, stereotypic
WordNet sense 4 (unimaginative and conformist):
conventional
From the ODE community, based on WordNet
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