deference vs courtesy

deference and courtesy both are nouns.

Word	Noun	Adjective	Verb	Adverb
deference	Yes	No	No	No
courtesy	Yes	No	No	No

As nouns, courtesy is a hypernym of deference; that is, courtesy is a word with a broader meaning than deference:

Other hypernyms of deference include good manners.

deference (noun)	courtesy (noun)
a courteous expression (by word or deed) of esteem or regard	a courteous or respectful or considerate act
a disposition or tendency to yield to the will of others	a courteous manner
courteous regard for people's feelings	a courteous or respectful or considerate remark