47 entries under theoretical topic. ×

2
insubstantial(abstract, shadowy, ghastly, ethereal)
2
mystical(adjective, obscure, perfect, marvelous, abstract)
2
numinous(obscure, dark, mysterious, abstract, heavenly)
2
superior(obscure, dark, marvelous, abstract, heavenly)
2
supranatural(adjective, obscure, dark, superior, amazing)
2
unphysical(abstract, abstruse, philosophical)
1
nonmaterial(abstract, heavenly, abstruse, philosophical)
1
abstruse(obscure, deep, mysterious, abstract)
1
conjectural(vague, abstract, academic, philosophical)
1
deep(obscure, mysterious, abstract, weird)
1
difficult(abstract, abstruse, philosophical)
1
eternal(perfect, marvelous, abstract, abstruse)
1
fundamental(abstract, abstruse, philosophical)
1
high-flown(adjective, intellectual, supernatural, abstract, spiritual)
1
hypothetical(adjective, vague, intellectual, supernatural, abstract)
1
intellectual(adjective, vague, supernatural, abstract, logical)
1
jesuitic(abstract, abstruse, philosophical)
1
oversubtle(abstract, abstruse, philosophical)
1
philosophical(abstract, abstruse, academic, hypothetical)
1
profound(obscure, deep, mysterious, abstract, weird)
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APASmart Define. (2016). unearthly thesaurus. Retrieved September 30, 2026, from https://smartdefine.org/unearthly/thesaurus/synonyms
ChicagoSmart Define. 2016. "unearthly thesaurus" https://smartdefine.org/unearthly/thesaurus/synonyms (accessed September 30, 2026).
HarvardSmart Define 2016, unearthly thesaurus, Smart Define, viewed 30 September, 2026, <https://smartdefine.org/unearthly/thesaurus/synonyms>.
MLASmart Define. "unearthly thesaurus" 31 March 2016. Web. 30 September 2026. <https://smartdefine.org/unearthly/thesaurus/synonyms>