Synonyms for Purposeless (same or very similar meaning)
WordNet sense 1 (marked by lack of definite plan or regularity or purpose; jumping from one thing to another):
desultory
WordNet sense 2 (aimlessly drifting):
aimless
WordNet sense 3 (lacking import):
pointless, senseless
WordNet sense 4 (having no meaning or direction or purpose):
meaningless, nonmeaningful
From the ODE community, based on WordNet
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