secret writing vs cryptograph

secret writing and cryptograph both are nouns.

Word	Noun	Adjective	Verb	Adverb
secret writing	Yes	No	No	No
cryptograph	Yes	No	No	No

As nouns, secret writing and cryptograph are synonyms defined as:

Other synonyms of secret writing include cryptogram.

secret writing (noun)	cryptograph (noun)
act of writing in code or cipher	a device for deciphering codes and ciphers
a piece of writing in code or cipher	a piece of writing in code or cipher
	a secret method of writing