cipher vs secret code

cipher and secret code both are nouns.

Word	Noun	Adjective	Verb	Adverb
cipher	Yes	No	Yes	No
secret code	Yes	No	No	No

As nouns, cipher and secret code are synonyms defined as:

Other synonyms of cipher include cryptograph, cypher.

cipher (noun)	secret code (noun)
a secret method of writing	a secret method of writing
a message written in a secret code
a person of no influence
a quantity of no importance; thing (object:), singular, negative pronoun; pronoun, thing, singular; quantifier: negative existential
a mathematical element that when added to another number yields the same number

cipher (verb)	secret code (verb)
make a mathematical calculation or computation
convert ordinary language into code