intransigency vs pigheadedness

intransigency and pigheadedness both are nouns.

Word	Noun	Adjective	Verb	Adverb
intransigency	Yes	No	No	No
pigheadedness	Yes	No	No	No

As nouns, pigheadedness is a hypernym of intransigency; that is, pigheadedness is a word with a broader meaning than intransigency:

intransigency: the trait of being intransigent; stubbornly refusing to compromise
pigheadedness: resolute adherence to your own ideas or desires

Other hypernyms of intransigency include bullheadedness, obstinacy, obstinance, self-will, stubbornness.

intransigency (noun)	pigheadedness (noun)
the trait of being intransigent; stubbornly refusing to compromise	resolute adherence to your own ideas or desires