behaviour, n. (US behavior)
1 a the way one conducts oneself; manners. b the treatment of others; moral conduct.
2 the way in which a ship, machine, chemical substance, etc., acts or works.
3 Psychol. the response (of a person, animal, etc.) to a stimulus.
behaviour therapy the treatment of neurotic symptoms by training the patient's reactions (see BEHAVIOURISM). be on one's good (or best) behaviour behave well when being observed.
BEHAVE after demeanour and obs. haviour f. have