internal organ

Definitions of internal organ
  1. noun
    a main organ that is situated inside the body
    synonyms: viscus
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    entrails, innards, viscera
    internal organs collectively (especially those in the abdominal cavity)
    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
    respiratory organ
    any organ involved in the process of respiration
    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
    flame cell
    organ of excretion in flatworms
    craw, crop
    a pouch in many birds and some lower animals that resembles a stomach for storage and preliminary maceration of food
    first stomach, rumen
    the first compartment of the stomach of a ruminant; here food is collected and returned to the mouth as cud for chewing
    reticulum, second stomach
    the second compartment of the stomach of a ruminant
    omasum, psalterium, third stomach
    the third compartment of the stomach of a ruminant
    abomasum, fourth stomach
    the fourth compartment of the stomach of a ruminant; the one where digestion takes place
    branchia, gill
    respiratory organ of aquatic animals that breathe oxygen dissolved in water
    either of two bean-shaped excretory organs that filter wastes (especially urea) from the blood and excrete them and water in urine
    either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood
    athlete's heart
    enlarged heart commonly found among athletes trained for endurance
    biauriculate heart
    a heart (as of mammals and birds and reptiles) having two auricles
    book lung
    organ in many arachnids containing many thin folds of membrane resembling the leaves of a book
    small intestine
    the longest part of the alimentary canal; where digestion is completed
    large intestine
    beginning with the cecum and ending with the rectum; includes the cecum and the colon and the rectum; extracts moisture from food residues which are later excreted as feces
    type of:
    a fully differentiated structural and functional unit in an animal that is specialized for some particular function
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