speaker

(noun) someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous). Synonyms: talker, utterer, verbalizer, verbaliser. Examples: "The speaker at commencement." "An utterer of useful maxims."

(noun) electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance. Synonyms: loudspeaker, speaker unit, loudspeaker system, speaker system.

(noun) the presiding officer of a deliberative assembly. Synonyms: Speaker. Example: "The leader of the majority party is the speaker of the house of representatives."