pendragon vs chieftain

pendragon and chieftain both are nouns.

Word	Noun	Adjective	Verb	Adverb
pendragon	Yes	No	No	No
chieftain	Yes	No	No	No

As nouns, chieftain is a hypernym of pendragon; that is, chieftain is a word with a broader meaning than pendragon:

Other hypernyms of pendragon include chief, headman, tribal chief.

pendragon (noun)	chieftain (noun)
the supreme war chief of the ancient Britons	the head of a tribe or clan
	the leader of a group of people