enigma vs mystery

enigma and mystery both are nouns.

Word	Noun	Adjective	Verb	Adverb
enigma	Yes	No	No	No
mystery	Yes	No	No	No

As nouns, enigma and mystery are synonyms defined as:

enigma and mystery: something that baffles understanding and cannot be explained

Other synonyms of enigma include closed book, secret.

enigma (noun)	mystery (noun)
something that baffles understanding and cannot be explained	something that baffles understanding and cannot be explained
a difficult problem	a story about a crime (usually murder) presented as a novel or play or movie