jumping-off place vs rootage

jumping-off place and rootage both are nouns.

Word	Noun	Adjective	Verb	Adverb
jumping-off place	Yes	No	No	No
rootage	Yes	No	No	No

As nouns, rootage is a hypernym of jumping-off place; that is, rootage is a word with a broader meaning than jumping-off place:

jumping-off place: a place from which an enterprise or expedition is launched
rootage: the place where something begins, where it springs into being

Other hypernyms of jumping-off place include beginning, origin, root, source.

jumping-off place (noun)	rootage (noun)
a place from which an enterprise or expedition is launched	the place where something begins, where it springs into being
	a developed system of roots
	fixedness by or as if by roots