germination vs ontogeny

germination and ontogeny both are nouns.

Word	Noun	Adjective	Verb	Adverb
germination	Yes	No	No	No
ontogeny	Yes	No	No	No

As nouns, ontogeny is a hypernym of germination; that is, ontogeny is a word with a broader meaning than germination:

germination: the process whereby seeds or spores sprout and begin to grow
ontogeny: (biology) the process of an individual organism growing organically; a purely biological unfolding of events involved in an organism changing gradually from a simple to a more complex level

Other hypernyms of germination include development, growing, growth, maturation, ontogenesis.

germination (noun)	ontogeny (noun)
the origin of some development	(biology) the process of an individual organism growing organically; a purely biological unfolding of events involved in an organism changing gradually from a simple to a more complex level
the process whereby seeds or spores sprout and begin to grow