An organ is a part of your body that performs a specific function: like your brain, lungs, or skin.

You might not use the word organ often, but you use organs every second; imagine getting through a day without your heart, lungs, or brain. Some people choose to be organ donors — meaning that, after their deaths, they donate their organs to people in need of organ transplants. An organ may also serve a specific function for an institution: a periodical like a newsletter can be an organ of an organization. An organ is also the wind instrument — sometimes called a pipe organ — often played in church.

Definitions of organ
  1. noun
    a fully differentiated structural and functional unit in an animal that is specialized for some particular function
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    egg-laying tubular structure at the end of the abdomen in many female insects and some fishes
    siphon, syphon
    a tubular organ in an aquatic animal (especially in mollusks) through which water can be taken in or expelled
    comb-plate, ctene
    a locomotor organ consisting of a row of strong cilia whose bases are fused
    a movable organ for flying (one of a pair)
    foot, invertebrate foot
    any of various organs of locomotion or attachment in invertebrates
    an organ specialized for sucking nourishment or for adhering to objects by suction
    a sharp organ of offense or defense (as of a wasp or stingray or scorpion) often connected with a poison gland
    contractile organ, contractor
    a bodily organ that contracts
    anlage, primordium
    an organ in its earliest stage of development; the foundation for subsequent development
    vital organ, vitals
    a bodily organ that is essential for life
    an organ (a gland or muscle) that becomes active in response to nerve impulses
    external organ
    an organ that is situated on or near the surface of the body
    internal organ, viscus
    a main organ that is situated inside the body
    receptor, sense organ, sensory receptor
    an organ having nerve endings (in the skin or viscera or eye or ear or nose or mouth) that respond to stimulation
    clapper, glossa, lingua, tongue
    a mobile mass of muscular tissue covered with mucous membrane and located in the oral cavity
    organ of speech, speech organ, vocal organ
    any of the organs involved in speech production
    crystalline lens, lens, lens of the eye
    biconvex transparent body situated behind the iris in the eye; its role (along with the cornea) is to focuses light on the retina
    gland, secreter, secretor, secretory organ
    any of various organs that synthesize substances needed by the body and release it through ducts or directly into the bloodstream
    cell organ, cell organelle, organelle
    a specialized part of a cell; analogous to an organ
    end organ
    a specialized structure at the peripheral end of some motor or sensory nerve fibers
    reproductive organ, sex organ
    any organ involved in sexual reproduction
    target organ
    (radiology) organ intended to receive the therapeutic dose of a radioactive substance
    taret organ
    (endocrinology) organ most affected by a particular hormone
    erectile organ
    an organ containing erectile tissue
    a hairlike projection from the surface of a cell; provides locomotion in free-swimming unicellular organisms
    a sharp-pointed process especially a sting of a hymenopterous insect
    green gland
    one of a pair of glands (believed to have excretory functions) in some crustaceans near the base of the large antennae
    a wing of an insect
    fore wing, fore-wing, forewing
    either of the anterior pair of wings on an insect that has four wings
    balancer, halter, haltere
    either of the rudimentary hind wings of dipterous insects; used for maintaining equilibrium during flight
    pennon, pinion
    wing of a bird
    elytron, wing case
    either of the horny front wings in beetles and some other insects which cover and protect the functional hind wings
    tube foot
    tentacular tubular process of most echinoderms (starfish and sea urchins and holothurians) having a sucker at the end and used for e.g. locomotion and respiration
    a sucker on the feet of certain flies
    lateral line, lateral line organ
    sense organs of fish and amphibians; believed to detect pressure changes in the water
    sericterium, serictery, silk gland
    silk-producing gland of insects (especially of a silkworm) or spiders
    muscle, musculus
    one of the contractile organs of the body
    entrails, innards, viscera
    internal organs collectively (especially those in the abdominal cavity)
    enteroceptor, interoceptor
    any receptor that responds to stimuli inside the body
    any receptor that responds to stimuli outside the body
    pineal eye, third eye
    a sensory structure capable of light reception located on the dorsal side of the diencephalon in various reptiles
    a sensory receptor that responds to pressure
    a sensory receptor that responds to chemical stimuli
    a sensory receptor that responds to heat and cold
    a movable speech organ
    the vocal apparatus of the larynx; the true vocal folds and the space between them where the voice tone is generated
    eye, oculus, optic
    the organ of sight
    the sense organ for hearing and equilibrium
    organ of hearing
    the part of the ear that is responsible for sensations of sound
    inner ear, internal ear, labyrinth
    a complex system of interconnecting cavities; concerned with hearing and equilibrium
    semicircular canal
    one of three tube loops filled with fluid and in planes nearly at right angles with one another; concerned with equilibrium
    stretch receptor
    a receptor in a muscle that responds to stretching of the muscle tissue
    external ear, outer ear
    the part of the ear visible externally
    duct gland, exocrine, exocrine gland
    a gland that secretes externally through a duct
    ductless gland, endocrine, endocrine gland
    any of the glands of the endocrine system that secrete hormones directly into the bloodstream
    excretory organ, urinary organ
    an organ that separates waste substances from the blood and discharges them
    large and complicated reddish-brown glandular organ located in the upper right portion of the abdominal cavity; secretes bile and functions in metabolism of protein and carbohydrate and fat; synthesizes substances involved in the clotting of the blood; synthesizes vitamin A; detoxifies poisonous substances and breaks down worn-out erythrocytes
    heart, pump, ticker
    the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions move the blood through the body
    breadbasket, stomach, tum, tummy
    an enlarged and muscular saclike organ of the alimentary canal; the principal organ of digestion
    an organelle found in the cytoplasm of most cells (especially in leukocytes and liver and kidney cells)
    cell nucleus, karyon, nucleus
    a part of the cell containing DNA and RNA and responsible for growth and reproduction
    nucleole, nucleolus
    a small round body of protein in a cell nucleus; such organelles contain RNA and are involved in protein synthesis
    chondriosome, mitochondrion
    an organelle containing enzymes responsible for producing energy
    one of a pair of small cylindrical cell organelles near the nucleus in animal cells; composed of nine triplet microtubules and form the asters during mitosis
    any of a group of particles in the cytoplasm of a living cell; they attach to mRNA and move down it one codon at a time and then stop until tRNA brings the required amino acid; when it reaches a stop codon it falls apart and releases the completed protein molecule for use by the cell
    end-plate, endplate, motor end plate
    the flattened end of a motor neuron that transmits neural impulses to a muscle
    sensory end organ that responds to changes in osmotic pressure
    the external surface of the body overlying the heart and stomach
    crotch, genital organ, genitalia, genitals, private parts, privates
    external sex organ
    female internal reproductive organ
    the reproductive organs of a woman
    male internal reproductive organ
    the reproductive organs of a man
    male reproductive gland
    the reproductive organs of a man
    the male organ of copulation (`member' is a euphemism)
    respiratory organ
    any organ involved in the process of respiration
    larynx, voice box
    a cartilaginous structure at the top of the trachea; contains elastic vocal cords that are the source of the vocal tone in speech
    bowel, gut, intestine
    the part of the alimentary canal between the stomach and the anus
    the caudal part of the alimentary canal in vertebrate embryos
    mamilla, mammilla, nipple, pap, teat, tit
    the small projection of a mammary gland
    type of:
    body part
    any part of an organism such as an organ or extremity
  2. noun
    a government agency or instrument devoted to the performance of some specific function
    “The Census Bureau is an organ of the Commerce Department”
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    type of:
    agency, authority, bureau, federal agency, government agency, office
    an administrative unit of government
  3. noun
    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
    synonyms: pipe organ
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    type of:
    keyboard instrument
    a musical instrument that is played by means of a keyboard
    wind, wind instrument
    a musical instrument in which the sound is produced by an enclosed column of air that is moved by the breath
  4. noun
    a free-reed instrument in which air is forced through the reeds by bellows
    synonyms: harmonium, reed organ
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    type of:
    free-reed instrument
    a wind instrument with a free reed
  5. noun
    (music) an electronic simulation of a pipe organ
    synonyms: Hammond organ, electric organ, electronic organ
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    type of:
    electronic instrument, electronic musical instrument
    a musical instrument that generates sounds electronically
  6. noun
    a periodical that is published by a special interest group
    “the organ of the communist party”
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    house organ
    a periodical published by a business firm for its employees and customers
    type of:
    a publication that appears at fixed intervals
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