Wiktionary
n. (label en American spelling) (alternative spelling of behaviouralism English)
Wikipedia
Behavioralism (or behaviouralism in British English) is an approach in political science, which emerged in the 1930s in the United States. It represents a sharp break from previous political science. This is because it emphasized an objective, quantified approach to explain and predict political behavior. It is associated with the rise of the behavioral sciences, modeled after the natural sciences. This means that behavioralism claims it can explain political behavior from an unbiased, neutral point of view.
Behavioralism seeks to examine the behavior, actions, and acts of individuals – rather than the characteristics of institutions such as legislatures, executives, and judiciaries – and groups in different social settings and explain this behavior as it relates to the political system.