sanction vs approve

sanction is a noun but approve is not a noun.

Word	Noun	Adjective	Verb	Adverb
sanction	Yes	No	Yes	No
approve	No	No	Yes	No

As verbs, sanction and approve are synonyms defined as:

Other synonyms of sanction include O.K., okay.

As verbs, approve is a hypernym of sanction; that is, approve is a word with a broader meaning than sanction:

Other hypernyms of sanction include O.K., okay, sanction.

sanction (noun)	approve (noun)
the act of final authorization
a mechanism of social control for enforcing a society's standards
official permission or approval
formal and explicit approval

sanction (verb)	approve (verb)
give sanction to	judge to be right or commendable; think well of
give religious sanction to, such as through an oath	give sanction to
give authority or permission to