decease vs asphyxiate

decease is a noun but asphyxiate is not a noun.

Word	Noun	Adjective	Verb	Adverb
decease	Yes	No	Yes	No
asphyxiate	No	No	Yes	No

As verbs, asphyxiate is a hyponym of decease; that is, asphyxiate is a word with a more specific, narrower meaning than decease:

decease: pass from physical life and lose all bodily attributes and functions necessary to sustain life
asphyxiate: be asphyxiated; die from lack of oxygen

Other hyponyms of decease include abort, stifle, suffocate, buy it, pip out, drown, predecease, famish, starve, fall, succumb, yield.

decease (noun)	asphyxiate (noun)
the event of dying or departure from life

decease (verb)	asphyxiate (verb)
pass from physical life and lose all bodily attributes and functions necessary to sustain life	be asphyxiated; die from lack of oxygen
	deprive of oxygen and prevent from breathing
	impair the respiration of or obstruct the air passage of