preferment vs promotion

preferment and promotion both are nouns.

Word	Noun	Adjective	Verb	Adverb
preferment	Yes	No	No	No
promotion	Yes	No	No	No

As nouns, promotion is a hypernym of preferment; that is, promotion is a word with a broader meaning than preferment:

preferment (noun)	promotion (noun)
the act of preferring	act of raising in rank or position
the act of making accusations	the advancement of some enterprise
	a message issued in behalf of some product or cause or idea or person or institution
	encouragement of the progress or growth or acceptance of something