append vs say

append is not a noun while say is a noun.

Word	Noun	Adjective	Verb	Adverb
append	No	No	Yes	No
say	Yes	No	Yes	No

As verbs, say is a hypernym of append; that is, say is a word with a broader meaning than append:

Other hypernyms of append include state, tell.

append (noun)	say (noun)
	the chance to speak

append (verb)	say (verb)
state or say further	express in words
fix to; attach	report or maintain
add to the very end	speak, pronounce, or utter in a certain way
	express a supposition
	give instructions to or direct somebody to do something with authority
	communicate or express nonverbally
	recite or repeat a fixed text
	indicate
	state as one's opinion or judgement; declare
	utter aloud
	have or contain a certain wording or form