https://www.merriam-webster.com/thesaurus/unsubstantial
UNSUBSTANTIAL Synonyms: 162 Similar and Opposite Words | Merriam-Webster Thesaurus
Synonyms for UNSUBSTANTIAL: spiritual, incorporeal, metaphysical, insubstantial, immaterial, supernatural, invisible, nonmaterial; Antonyms of UNSUBSTANTIAL:...
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