Synonyms for Meaningless (same or very similar meaning)
WordNet sense 1 (lacking import):
pointless, senseless
WordNet sense 2 (having no intelligible meaning):
nonsensical
WordNet sense 3 (signifying nothing):
insignificant, unmeaning
WordNet sense 4 (devoid of significance or point):
empty, hollow
WordNet sense 5 (having no meaning or direction or purpose):
nonmeaningful
From the ODE community, based on WordNet
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