noun
1. (music) an electronic simulation of a pipe organ
Synonym: electric organelectronic organHammond organ
2. a free-reed instrument in which air is forced through the reeds by bellows
Synonym: harmoniumreed organ
3. 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
Synonym: pipe organ
4. a fully differentiated structural and functional unit in an animal that is specialized for some particular function
5. a periodical that is published by a special interest group
e.g. the organ of the communist party
6. a government agency or instrument devoted to the performance of some specific function
e.g. The Census Bureau is an organ of the Commerce Department