decoder vs cryptanalyst

decoder and cryptanalyst both are nouns.

Word	Noun	Adjective	Verb	Adverb
decoder	Yes	No	No	No
cryptanalyst	Yes	No	No	No

As nouns, cryptanalyst is a hyponym of decoder; that is, cryptanalyst is a word with a more specific, narrower meaning than decoder:

decoder: the kind of intellectual who converts messages from a code to plain text
cryptanalyst: decoder skilled in the analysis of codes and cryptograms

Other hyponyms of decoder include cryptographer, cryptologist.

decoder (noun)	cryptanalyst (noun)
a machine that converts a coded text into ordinary language	decoder skilled in the analysis of codes and cryptograms
the kind of intellectual who converts messages from a code to plain text