ethician vs philosopher

ethician and philosopher both are nouns.

Word	Noun	Adjective	Verb	Adverb
ethician	Yes	No	No	No
philosopher	Yes	No	No	No

As nouns, philosopher is a hypernym of ethician; that is, philosopher is a word with a broader meaning than ethician:

ethician (noun)	philosopher (noun)
a philosopher who specializes in ethics	a specialist in philosophy
	a wise person who is calm and rational; someone who lives a life of reason with equanimity