Synonyms for Behavior (same or very similar meaning)
WordNet sense 1 (the action or reaction of something (as a machine or substance) under specified circumstances):
behaviour
WordNet sense 2 ((behavioral attributes) the way a person behaves toward other people):
conduct, demeanor, deportment, demeanour, conduct
WordNet sense 3 (manner of acting or controlling yourself):
doings
From the ODE community, based on WordNet
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