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

organ \or"gan\ ^or"gan, n. l. organum, gr. 'o`rganon; akin
   to 'e`rgon work, and e. work: cf. f. organe. see work, and
   cf. orgue, orgy.
   1. an instrument or medium by which some important action is
      performed, or an important end accomplished; as,
      legislatures, courts, armies, taxgatherers, etc., are
      organs of government.
      1913 webster

   2. biol. a natural part or structure in an animal or a
      plant, capable of performing some special action termed
      its function, which is essential to the life or
      well-being of the whole; as, the heart, lungs, etc., are
      organs of animals; the root, stem, foliage, etc., are
      organs of plants.
      1913 webster

   note: in animals the organs are generally made up of several
         tissues, one of which usually predominates, and
         determines the principal function of the organ. groups
         of organs constitute a system. see system.
         1913 webster

   3. a component part performing an essential office in the
      working of any complex machine; as, the cylinder, valves,
      crank, etc., are organs of the steam engine.
      1913 webster

   4. a medium of communication between one person or body and
      another; as, the secretary of state is the organ of
      communication between the government and a foreign power;
      a newspaper is the organ of its editor, or of a party,
      sect, etc. a newsletter distributed within an organization
      is often called its house organ.
      1913 webster +pjc

   5. cf. as. organ, fr. l. organum. mus. a wind instrument
      containing numerous pipes of various dimensions and kinds,
      which are filled with wind from a bellows, and played upon
      by means of keys similar to those of a piano, and
      sometimes by foot keys or pedals; -- formerly used in the
      plural, each pipe being considered an organ.
      1913 webster

            the deep, majestic, solemn organs blow. --pope.
      1913 webster

   note: chaucer used the form orgon as a plural.
         1913 webster

               the merry orgon . . . that in the church goon
               go.
         1913 webster

   barrel organ, choir organ, great organ, etc. see under
      barrel, choir, etc.

   cabinet organ mus., an organ of small size, as for a
      chapel or for domestic use; a reed organ.

   organ bird zool., a tasmanian crow shrike gymnorhina
      organicum. it utters discordant notes like those of a
      hand organ out of tune.

   organ fish zool., the drumfish.

   organ gun. mil. same as orgue
      b .

   organ harmonium mus., an harmonium of large capacity and
      power.

   organ of corti anat., a complicated structure in the
      cochlea of the ear, including the auditory hair cells, the
      rods or fibers of corti, the membrane of corti, etc. see
      note under ear.

   organ pipe. see pipe, n., 1.

   organ-pipe coral. zool. see tubipora.

   organ point mus., a passage in which the tonic or
      dominant is sustained continuously by one part, while the
      other parts move.
      1913 webster
see also:
work orgue orgy system house organ barrel organ 
choir organ great organ barrel choir cabinet organ 
organ bird gymnorhina organicum organ fish organ gun organ harmonium 
organ of corti ear organ pipe pipe organ-pipe coral 
tubipora organ point 

[2] : WordNet (r) 2.0

organ of corti
     n : the hearing organ of the inner ear; contains receptors that
         respond to sound waves

House Organ >> H Words
House Organ, definition of term: House Organ
house+organ_pag1.html