discourtesy vs message

discourtesy and message both are nouns.

Word	Noun	Adjective	Verb	Adverb
discourtesy	Yes	No	No	No
message	Yes	No	Yes	No

As nouns, message is a hypernym of discourtesy; that is, message is a word with a broader meaning than discourtesy:

Other hypernyms of discourtesy include content, subject matter, substance.

discourtesy (noun)	message (noun)
a lack of politeness; a failure to show regard for others; wounding the feelings of others	content communicating a message; what something is about
a manner that is rude and insulting	a communication (usually brief) that is written or spoken or signaled
an expression of lack of respect