successor vs peer

successor and peer both are nouns.

Word	Noun	Adjective	Verb	Adverb
successor	Yes	No	No	No
peer	Yes	No	Yes	No

As nouns, peer is a hypernym of successor; that is, peer is a word with a broader meaning than successor:

Other hypernyms of successor include compeer, equal, match.

successor (noun)	peer (noun)
a thing or person that immediately replaces something or someone	a person who is of equal standing with another in a group
a person who inherits some title or office	a nobleman (duke or marquis or earl or viscount or baron) who is a member of the British peerage
a person who follows next in order

successor (verb)	peer (verb)
	look searchingly