discourtesy vs insult

discourtesy and insult both are nouns.

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

As nouns, insult is a hyponym of discourtesy; that is, insult is a word with a more specific, narrower meaning than discourtesy:

discourtesy: a lack of politeness; a failure to show regard for others; wounding the feelings of others
insult: a deliberately offensive act or something producing the effect of deliberate disrespect

Other hyponyms of discourtesy include derision, ridicule, indelicacy, insolence, affront, presumption, rebuff, slight.

As nouns, insult is a hyponym of discourtesy; that is, insult is a word with a more specific, narrower meaning than discourtesy:

discourtesy (noun)	insult (noun)
a lack of politeness; a failure to show regard for others; wounding the feelings of others	a deliberately offensive act or something producing the effect of deliberate disrespect
a manner that is rude and insulting	a rude expression intended to offend or hurt
an expression of lack of respect

discourtesy (verb)	insult (verb)
	treat, mention, or speak to rudely