secret writing vs writing

secret writing and writing both are nouns.

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

As nouns, writing is a hypernym of secret writing; that is, writing is a word with a broader meaning than secret writing:

Other hypernyms of secret writing include committal to writing.

As nouns, writing is a hypernym of secret writing; that is, writing is a word with a broader meaning than secret writing:

secret writing: a piece of writing in code or cipher
writing: the work of a writer; anything expressed in letters of the alphabet (especially when considered from the point of view of style and effect)

Other hypernyms of secret writing include piece of writing, written material.

secret writing (noun)	writing (noun)
act of writing in code or cipher	the activity of putting something in written form
a piece of writing in code or cipher	the act of creating written works
	the work of a writer; anything expressed in letters of the alphabet (especially when considered from the point of view of style and effect)
	letters or symbols that are written or imprinted on a surface to represent the sounds or words of a language
	(usually plural) the collected work of an author