doubter vs intellectual

doubter and intellectual both are nouns.

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

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

Other hypernyms of doubter include intellect.

doubter (noun)	intellectual (noun)
someone who habitually doubts accepted beliefs	a person who uses the mind creatively
someone who is doubtful or noncommittal about something

doubter (adjective)	intellectual (adjective)
	appealing to or using the intellect
	involving intelligence rather than emotions or instinct
	of or associated with or requiring the use of the mind