Synonyms for Fantastical (same or very similar meaning)
WordNet sense 1 (existing in fancy only):
fantastic
WordNet sense 2 (lacking in reality or substance or genuineness; not corresponding to acknowledged facts or criteria):
unreal
WordNet sense 3 (ludicrously odd):
antic, grotesque
WordNet sense 4 (being definitely out of the ordinary and unexpected; slightly odd or even a bit weird):
strange, unusual
From the ODE community, based on WordNet
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