priest vs Druid

priest and Druid both are nouns.

Word	Noun	Adjective	Verb	Adverb
priest	Yes	No	No	No
Druid	Yes	No	No	No

As nouns, Druid is a hyponym of priest; that is, Druid is a word with a more specific, narrower meaning than priest:

priest: a person who performs religious duties and ceremonies in a non-Christian religion
Druid: a pre-Christian priest among the Celts of ancient Gaul and Britain and Ireland

Other hyponyms of priest include flamen, hoodoo, lama, magus, priest-doctor, shaman, votary.

priest (noun)	Druid (noun)
a clergyman in Christian churches who has the authority to perform or administer various religious rites; one of the Holy Orders	a pre-Christian priest among the Celts of ancient Gaul and Britain and Ireland
a person who performs religious duties and ceremonies in a non-Christian religion