defense reaction vs defense mechanism

defense reaction and defense mechanism both are nouns.

Word	Noun	Adjective	Verb	Adverb
defense reaction	Yes	No	No	No
defense mechanism	Yes	No	No	No

As nouns, defense reaction and defense mechanism are synonyms defined as:

defense reaction and defense mechanism: (psychiatry) an unconscious process that tries to reduce the anxiety associated with instinctive desires

Other synonyms of defense reaction include defence, defence mechanism, defence reaction, defense.

defense reaction (noun)	defense mechanism (noun)
(psychiatry) an unconscious process that tries to reduce the anxiety associated with instinctive desires	(psychiatry) an unconscious process that tries to reduce the anxiety associated with instinctive desires