buy the farm vs stifle

buy the farm is not a noun while stifle is a noun.

Word	Noun	Adjective	Verb	Adverb
buy the farm	No	No	Yes	No
stifle	Yes	No	Yes	No

As verbs, stifle is a hyponym of buy the farm; that is, stifle is a word with a more specific, narrower meaning than buy the farm:

buy the farm: pass from physical life and lose all bodily attributes and functions necessary to sustain life
stifle: be asphyxiated; die from lack of oxygen

Other hyponyms of buy the farm include abort, asphyxiate, suffocate, buy it, pip out, drown, predecease, famish, starve, fall, succumb, yield.

buy the farm (noun)	stifle (noun)
	joint between the femur and tibia in a quadruped; corresponds to the human knee

buy the farm (verb)	stifle (verb)
pass from physical life and lose all bodily attributes and functions necessary to sustain life	suppress or constrain so as to lessen in intensity
	be asphyxiated; die from lack of oxygen
	suppress in order to conceal or hide
	impair the respiration of or obstruct the air passage of