Synonyms for Demonstrative (same or very similar meaning)
WordNet sense 1 (a pronoun that points out an intended referent):
demonstrative pronoun
WordNet sense 2 (serving to demonstrate):
illustrative
WordNet sense 3 (serving to instruct of enlighten or inform):
informative, instructive
WordNet sense 4 (extravagantly demonstrative):
effusive, emotional
From the ODE community, based on WordNet
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