1. [n]  (music) an electronic simulation of a pipe organ
2. [n]  a free-reed instrument in which air is forced through the reeds by bellows
3. [n]  wind instrument whose sound is produced by means of pipes arranged in sets supplied with air from a bellows and controlled from a large complex musical keyboard
4. [n]  a fully differentiated structural and functional unit in an animal that is specialized for some particular function
5. [n]  a periodical that is published by a special interest group; "the organ of the communist party"
6. [n]  a government agency or instrument devoted to the performance of some specific function; "The Census Bureau is an organ of the Commerce Department"

Organ
Organ

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1. \Or"gan\, n. [L. organum, Gr. ?; akin to ? 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.
   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.
   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}.
   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.
   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.
   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 considired an organ.
            The deep, majestic, solemn organs blow. --Pope.
   Note: Chaucer used the form orgon as a plural.
               The merry orgon . . . that in the church goon
               [go].
   {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} (Zo["o]l.), a Tasmanian crow shrike ({Gymnorhina
      organicum}). It utters discordant notes like those of a
      hand organ out of tune.
   {Organ fish} (Zo["o]l.), the drumfish.
   {Organ gun}. (Mil.) Same as {Orgue}
      (b) .
   {Organ harmonium} (Mus.), an harmonium of large capacity and
      power.
   {Organ of Gorti} (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}. (Zo["o]l.) See {Tubipora}.
   {Organ point} (Mus.), a passage in which the tonic or
      dominant is sustained continuously by one part, while the
      other parts move.
   

2. \Or"gan\, v. t.
   To supply with an organ or organs; to fit with organs; to
   organize. [Obs.]
         Thou art elemented and organed for other apprehensions.
                                                  --Bp.
                                                  Mannyngham.
   

some kind of wind instrument, probably a kind of Pan's pipes (Gen. 4:21; Job 21:12; Ps. 150:4), which consisted of seven or eight reeds of unequal length.