The term speaker is a title often given to the presiding officer of a legislative body. The speaker's official role is to moderate debate, make rulings on procedure, announce the results of votes, and the like. The speaker decides who may speak and has the powers to discipline members who break the procedures of the house. The speaker often also represents the body in his or her person, as the voice of the body in ceremonial and some other situations.

As a parliamentary title it is typically Anglo-Saxon, first recorded in the English parliament for Thomas de Hungerford in 1377; in most other cultures other styles are used, mainly translations of Chairman or President.

Many bodies also have a Speaker pro Tempore or temporary Speaker designated to fill in when the Speaker is not available.