Satan vs Lucifer

Satan and Lucifer both are nouns.

Word	Noun	Adjective	Verb	Adverb
Satan	Yes	No	No	No
Lucifer	Yes	No	No	No

As nouns, Satan and Lucifer are synonyms defined as:

Satan and Lucifer: (Judeo-Christian and Islamic religions) chief spirit of evil and adversary of God; tempter of mankind; master of Hell

Other synonyms of Satan include Beelzebub, Devil, Old Nick, Prince of Darkness, the Tempter.

Satan (noun)	Lucifer (noun)
(Judeo-Christian and Islamic religions) chief spirit of evil and adversary of God; tempter of mankind; master of Hell	a planet (usually Venus) seen just before sunrise in the eastern sky
	(Judeo-Christian and Islamic religions) chief spirit of evil and adversary of God; tempter of mankind; master of Hell