repress vs stifle

repress is not a noun while stifle is a noun.

Word	Noun	Adjective	Verb	Adverb
repress	No	No	Yes	No
stifle	Yes	No	Yes	No

As verbs, repress and stifle are synonyms defined as:

Other synonyms of repress include muffle, smother, strangle.

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

repress (verb)	stifle (verb)
block the action of	suppress or constrain so as to lessen in intensity
put out of one's consciousness	be asphyxiated; die from lack of oxygen
suppress in order to conceal or hide	suppress in order to conceal or hide
put down by force or intimidation	impair the respiration of or obstruct the air passage of
impede or hinder the natural development or self-expression of