stonewaller vs thwarter

stonewaller and thwarter both are nouns.

Word	Noun	Adjective	Verb	Adverb
stonewaller	Yes	No	No	No
thwarter	Yes	No	No	No

As nouns, thwarter is a hypernym of stonewaller; that is, thwarter is a word with a broader meaning than stonewaller:

stonewaller: one who stonewalls or refuses to answer or cooperate; someone who delays by lengthy speeches etc.
thwarter: someone who systematically obstructs some action that others want to take

Other hypernyms of stonewaller include obstructer, obstructionist, obstructor, resister.

stonewaller (noun)	thwarter (noun)
one who stonewalls or refuses to answer or cooperate; someone who delays by lengthy speeches etc.	someone who systematically obstructs some action that others want to take