adoption vs approval

adoption and approval both are nouns.

Word	Noun	Adjective	Verb	Adverb
adoption	Yes	No	No	No
approval	Yes	No	No	No

As nouns, approval is a hypernym of adoption; that is, approval is a word with a broader meaning than adoption:

Other hypernyms of adoption include approving, blessing.

adoption (noun)	approval (noun)
the act of accepting with approval; favorable reception	the formal act of approving
the appropriation (of ideas or words etc) from another source	a message expressing a favorable opinion
a legal proceeding that creates a parent-child relation between persons not related by blood; the adopted child is entitled to all privileges belonging to a natural child of the adoptive parents (including the right to inherit)	a feeling of liking something or someone good
	acceptance as satisfactory