fertilized egg vs animate being

fertilized egg and animate being both are nouns.

Word	Noun	Adjective	Verb	Adverb
fertilized egg	Yes	No	No	No
animate being	Yes	No	No	No

As nouns, animate being is a hypernym of fertilized egg; that is, animate being is a word with a broader meaning than fertilized egg:

fertilized egg: an animal organism in the early stages of growth and differentiation that in higher forms merge into fetal stages but in lower forms terminate in commencement of larval life
animate being: a living organism characterized by voluntary movement

Other hypernyms of fertilized egg include animal, beast, brute, creature, fauna.

fertilized egg (noun)	animate being (noun)
an animal organism in the early stages of growth and differentiation that in higher forms merge into fetal stages but in lower forms terminate in commencement of larval life	a living organism characterized by voluntary movement