pig-headedly vs obstinately

pig-headedly and obstinately both are adverbs.

Word	Noun	Adjective	Verb	Adverb
pig-headedly	No	No	No	Yes
obstinately	No	No	No	Yes

As adverbs, pig-headedly and obstinately are synonyms defined as:

Other synonyms of pig-headedly include cussedly, mulishly, obdurately, stubbornly.

pig-headedly (adverb)	obstinately (adverb)
in a stubborn unregenerate manner	in a stubborn unregenerate manner