doubter vs intellect

doubter and intellect both are nouns.

Word	Noun	Adjective	Verb	Adverb
doubter	Yes	No	No	No
intellect	Yes	No	No	No

As nouns, intellect is a hypernym of doubter; that is, intellect is a word with a broader meaning than doubter:

Other hypernyms of doubter include intellectual.

doubter (noun)	intellect (noun)
someone who habitually doubts accepted beliefs	the capacity for rational thought or inference or discrimination
someone who is doubtful or noncommittal about something	knowledge and intellectual ability
	a person who uses the mind creatively