What does behavior mean?
Behavior is a noun describing the way in which a person, animal, machine, or system acts or conducts itself, whether in response to other people, external events, or internal states. In everyday use it often carries a judgment about propriety: we speak of 'good behavior,' 'bad behavior,' or being on one's best behavior, especially with children or in formal settings. In scientific contexts—psychology, biology, ethology, and even computer science—the word takes on a more neutral, observational tone, denoting measurable patterns of action or reaction. Derived forms include behavioral (adjective), misbehavior (noun), and behaviorism (the psychological school founded by John B. Watson). The word traces back through Middle English to the idea of 'having' or 'holding' oneself in a certain way. Because it bridges ordinary social judgment and rigorous scientific study, behavior remains one of the most versatile and frequently used nouns in English.
The manner in which someone conducts themselves, especially in relation to standards of politeness or morality.
"She was rewarded at school for her exemplary behavior."
Often used in evaluative contexts such as praising children or discussing discipline.
The observable activity or reaction of an organism, person, animal, machine, or system in response to stimuli or circumstances.
"Researchers recorded the dolphins' behavior over several months."
Common in scientific and technical writing; plural 'behaviors' frequently appears here.
The plural 'behaviors' is used chiefly in scientific or analytical writing when referring to multiple distinct types or instances of behavior. In general conversation, 'behavior' is treated as uncountable.
"The study catalogued dozens of feeding behaviors across the species."
"Behavior" was born from a simple idea — that to behave is literally to "have oneself" — making every act of good manners a small act of self-possession.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of behavior
Behavior derives from the verb 'behave,' which entered English in the late Middle Ages from the combination of the prefix 'be-' and 'have,' originally meaning to 'have' or 'bear' oneself in a particular way. The noun form emerged in the 15th–16th centuries, initially carrying connotations of conduct and deportment before broadening to include any pattern of action. Cognates appear in French ('avoir,' 'se comporter') reflecting the shared root in Old French and Latin 'habere' (to have). The spelling variant 'behaviour' reflects British convention influenced by French orthography.
Related word forms
How behavior is actually used
In American English, the standard spelling is 'behavior'; British English uses 'behaviour'. The word is neutral in register and can be used in both formal and informal contexts. In academic contexts such as psychology and biology, it often carries a technical sense referring to measurable responses of organisms. The plural form 'behaviors' is common in scientific writing but rare in everyday speech, where 'behavior' is usually treated as uncountable.
Easily confused with behavior
Beehive is a noun meaning a structure housing bees, whereas behavior refers to how someone or something acts; they share similar sounds but entirely unrelated meanings.