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Synonyms for Otiose (same or very similar meaning)

WordNet sense 1 (serving no useful purpose; having no excuse for being):
pointless, superfluous, wasted

WordNet sense 2 (lacking in usefulness or value):

WordNet sense 3 (producing no result or effect):
futile, ineffectual, unavailing

WordNet sense 4 (having no beneficial use or incapable of functioning usefully):

WordNet sense 5 (disinclined to work or exertion):
faineant, indolent, lazy, slothful, work-shy

WordNet sense 6 (not in action or at work):

From the ODE community, based on WordNetadd/edit