WordNet (r) 3.0 (2006):

behaviour
    n 1: the action or reaction of something (as a machine or
         substance) under specified circumstances; "the behavior of
         small particles can be studied in experiments" [syn:
         behavior, behaviour]
    2: (behavioral attributes) the way a person behaves toward other
       people [syn: demeanor, demeanour, behavior,
       behaviour, conduct, deportment]
    3: (psychology) the aggregate of the responses or reactions or
       movements made by an organism in any situation [syn:
       behavior, behaviour]
    4: manner of acting or controlling yourself [syn: behavior,
       behaviour, conduct, doings]