(n.) One who announces.

AFTRA DJ MC adviser ancestor anchor anchor man anchorman annunciator antecedent authority avant-garde bellman bellwether broadcaster buccinator buccinator novi temporis bushwhacker channel commentator communicant communicator crier disk jockey emcee enlightener enunciator expert witness explorer forebear foregoer forerunner foreshadower front runner frontiersman fugleman gossipmonger grapevine groundbreaker guide harbinger herald informant information center information medium informer innovator interviewee lead runner leader master of ceremonies messenger monitor mouthpiece news commentator newscaster newsmonger notifier nunciate pathfinder pioneer point precedent precursor predecessor premonitor presager presenter press proclaimer program director programmer public relations officer publisher radio radiobroadcaster reporter scout sound-effects man source spokesman sportscaster stormy petrel television teller tipster tout town crier trailblazer trailbreaker vanguard vaunt-courier voortrekker weatherman witness