Synonyms for Notional (same or very similar meaning)
WordNet sense 1 (not based on fact; dubious):
fanciful, imaginary, imagined
WordNet sense 2 (lacking in reality or substance or genuineness; not corresponding to acknowledged facts or criteria):
unreal
WordNet sense 3 (not based on fact or investigation):
speculative
WordNet sense 4 (concerned primarily with theories or hypotheses rather than practical considerations):
theoretic, theoretical
WordNet sense 5 (having the ability or power to create):
creative, originative
WordNet sense 6 (being of the nature of a notion or concept):
conceptional, ideational
WordNet sense 7 (existing only in the mind; separated from embodiment):
abstract, abstract
From the ODE community, based on WordNet
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