Synonyms for Antisocial (same or very similar meaning)
WordNet sense 1 (not inclined to society or companionship):
unsociable
WordNet sense 2 (hostile to or disruptive of normal standards of social behavior):
asocial
WordNet sense 3 (not seeking or given to association; being or living without companions):
unsocial
From the ODE community, based on WordNet
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