The noun speaker has 3 senses (first 3 from tagged texts)
1. (9) speaker, talker, utterer, verbalizer, verbaliser -- (someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous); "the speaker at commencement"; "an utterer of useful maxims")
2. (2) loudspeaker, speaker, speaker unit, loudspeaker system, speaker system -- (electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance)
3. (1) Speaker -- (the presiding officer of a deliberative assembly; "the leader of the majority party is the Speaker of the House of Representatives")