[1] : The Collaborative International Dictionary of English v.0.48

speaker \speak"er\, n.
   1. one who speaks. specifically:
      a one who utters or pronounces a discourse; usually, one
          who utters a speech in public; as, the man is a good
          speaker, or a bad speaker.
      b one who is the mouthpiece of others; especially, one
          who presides over, or speaks for, a delibrative
          assembly, preserving order and regulating the debates;
          as, the speaker of the house of commons, originally,
          the mouthpiece of the house to address the king; the
          speaker of a house of representatives.
          1913 webster

   2. a book of selections for declamation. u. s.
      1913 webster

[2] : WordNet (r) 2.0

speaker
     n 1: 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" syn: talker,
           utterer, verbalizer, verbaliser
     2: electro-acoustic transducer that converts electrical signals
        into sounds loud enough to be heard at a distance syn: loudspeaker,
         speaker unit, loudspeaker system, speaker system
     3: the presiding officer of a deliberative assembly; "the
        leader of the majority party is the speaker of the house
        of representatives"
see also:
talker utterer verbalizer verbaliser loudspeaker speaker unit 
loudspeaker system speaker system 

[3] : Moby Thesaurus II by Grady Ward, 1.0

71 moby thesaurus words for "speaker":
   acoustical network, capacitor speaker, chair, chairman, chatterbox,
   coaxial speaker, cone, convener, conversationalist,
   crossover network, debater, declaimer, demagogue, diaphragm,
   dynamic speaker, earphone, electrodynamic speaker,
   electromagnetic speaker, electrostatic speaker,
   excited-field speaker, full-fidelity speaker, haranguer, headphone,
   headset, herald, high-fidelity speaker, high-frequency speaker,
   horn, jawsmith, keynoter, lecturer, loudspeaker,
   low-frequency speaker, midrange speaker, monorange speaker, mouth,
   mouthpiece, moving-coil speaker, official spokesman, orator,
   panelist, patterer, permanent magnet speaker, presiding officer,
   prolocutor, prolocutress, prolocutrix, public speaker,
   rabble-rouser, ranter, rapporteur, reporter, sayer, speaker system,
   speaker unit, speecher, speechifier, speechmaker, spieler,
   spokesman, spokesperson, spokeswoman, spouter, talker,
   triaxial speaker, tub-thumper, tweeter, utterer, voice, voice coil,
   woofer

[4] : The Free On-line Dictionary of Computing (27 SEP 03)

speaker
     
        1.  loudspeaker.
     
        2. the person who is assumed to be talking.
     
        1996-12-01
     
     
see also:
loudspeaker 

Speaker >> S Words
Speaker, definition of term: Speaker
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