successor vs offspring

successor and offspring both are nouns.

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

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

Other hypernyms of successor include issue, progeny.

successor (noun)	offspring (noun)
a thing or person that immediately replaces something or someone	any immature animal
a person who inherits some title or office	something that comes into existence as a result
a person who follows next in order	the immediate descendants of a person