priestess vs priest

priestess and priest both are nouns.

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

As nouns, priest is a hypernym of priestess; that is, priest is a word with a broader meaning than priestess:

priestess: a woman priest
priest: a clergyman in Christian churches who has the authority to perform or administer various religious rites; one of the Holy Orders

Other hypernyms of priestess include adult female, woman.

priestess (noun)	priest (noun)
a woman priest	a clergyman in Christian churches who has the authority to perform or administer various religious rites; one of the Holy Orders
	a person who performs religious duties and ceremonies in a non-Christian religion