informant vs utterer

informant and utterer both are nouns.

Word	Noun	Adjective	Verb	Adverb
informant	Yes	No	No	No
utterer	Yes	No	No	No

As nouns, utterer is a hypernym of informant; that is, utterer is a word with a broader meaning than informant:

informant: someone who sees an event and reports what happened
utterer: someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)

Other hypernyms of informant include beholder, observer, perceiver, percipient, speaker, talker, verbaliser, verbalizer.

informant (noun)	utterer (noun)
a person who supplies information	someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous)
someone who sees an event and reports what happened	someone who circulates forged banknotes or counterfeit coins
	an organism that can utter vocal sounds