secrecy vs mum

secrecy and mum both are nouns.

Word	Noun	Adjective	Verb	Adverb
secrecy	Yes	No	No	No
mum	Yes	Yes	No	No

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

Other hyponyms of secrecy include enigmaticness.

secrecy (noun)	mum (noun)
the trait of keeping things secret	secrecy
the condition of being concealed or hidden	informal terms for a mother
	of China

secrecy (adjective)	mum (adjective)
	failing to speak or communicate etc when expected to