The term "instinctive reflex" refers to an automatic and immediate response to a stimulus, which is innate within an organism. There are several synonyms that one can use for "instinctive reflex," including "innate response," "innate behavior," and "instinctual reaction." Other related terms include "fixed action pattern," "instinctive behavior," and "reflex action." These terms are often used in the context of animal behavior and physiology, as they describe the automatic and involuntary actions that are essential for survival. Essentially, these terms refer to the natural and hardwired responses that organisms exhibit in order to adapt and thrive in their respective environments.