physiological reaction vs reflex action

physiological reaction and reflex action both are nouns.

Word	Noun	Adjective	Verb	Adverb
physiological reaction	Yes	No	No	No
reflex action	Yes	No	No	No

As nouns, physiological reaction and reflex action are synonyms defined as:

physiological reaction and reflex action: an automatic instinctive unlearned reaction to a stimulus

Other synonyms of physiological reaction include inborn reflex, innate reflex, instinctive reflex, reflex, reflex response, unconditioned reflex.

physiological reaction (noun)	reflex action (noun)
an automatic instinctive unlearned reaction to a stimulus	an automatic instinctive unlearned reaction to a stimulus