behaviorとは何ですか？ behaviorとは何ですか？ The manner in which one behaves.The actions or reactions of a person or animal in response to external or internal stimuli.One of these actions or reactions: "a hormone . . . known to directly control sex-specific reproductive and parenting behaviors in a wide variety of vertebrates” ( Thomas Maugh II). The manner in which something functions or operates: the faulty behavior of a computer program; the behavior of dying stars.