keynote vs speak

keynote is a noun but speak is not a noun.

Word	Noun	Adjective	Verb	Adverb
keynote	Yes	No	Yes	No
speak	No	No	Yes	No

As verbs, speak is a hypernym of keynote; that is, speak is a word with a broader meaning than keynote:

Other hypernyms of keynote include address.

keynote (noun)	speak (noun)
a fundamental or central idea
(music) the first note of a diatonic scale
the principal theme in a speech or literary work

keynote (verb)	speak (verb)
set the keynote of	express in speech
give the keynote address to (an audience)	exchange thoughts; talk with
	use language
	give a speech to
	make a characteristic or natural sound