decipherment vs steganography

decipherment and steganography both are nouns.

Word	Noun	Adjective	Verb	Adverb
decipherment	Yes	No	No	No
steganography	Yes	No	No	No

As nouns, steganography is a hypernym of decipherment; that is, steganography is a word with a broader meaning than decipherment:

decipherment: the activity of making clear or converting from code into plain text
steganography: act of writing in code or cipher

Other hypernyms of decipherment include coding, cryptography, secret writing.

decipherment (noun)	steganography (noun)
the activity of making clear or converting from code into plain text	act of writing in code or cipher