The word speaker has a number of uses:

• In politics the Speaker is the presiding officer in many legislative bodies.
• A loudspeaker is an electronic device used to transform varying electric current into audible sound.
• In linguistics, a speaker is the utterer of a message, and is typically the center of deixis in the message. A speaker is referred with the first-person pronoun by himself or herself.
• Also in linguistics, a speaker is a user of a spoken language, as opposed to a signer, a user of a sign language.
• A speaker can also be someone giving a speech, or lecture, see also public speaking.