Old Nick vs Prince of Darkness

Old Nick and Prince of Darkness both are nouns.

Word	Noun	Adjective	Verb	Adverb
Old Nick	Yes	No	No	No
Prince of Darkness	Yes	No	No	No

As nouns, Old Nick and Prince of Darkness are synonyms defined as:

Old Nick and Prince of Darkness: (Judeo-Christian and Islamic religions) chief spirit of evil and adversary of God; tempter of mankind; master of Hell

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

Old Nick (noun)	Prince of Darkness (noun)
(Judeo-Christian and Islamic religions) chief spirit of evil and adversary of God; tempter of mankind; master of Hell	(Judeo-Christian and Islamic religions) chief spirit of evil and adversary of God; tempter of mankind; master of Hell