speak vs speech

speak is not a noun while speech is a noun.

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

speak (noun)	speech (noun)
	the mental faculty or power of vocal communication
	(language) communication by word of mouth
	the act of delivering a formal spoken communication to an audience
	words making up the dialogue of a play
	a lengthy rebuke
	the exchange of spoken words
	your characteristic style or manner of expressing yourself orally
	something spoken

speak (verb)	speech (verb)
express in speech
exchange thoughts; talk with
use language
give a speech to
make a characteristic or natural sound