Definition of Endoscope :an illuminated usually fiber-optic flexible or rigid tubular instrument for visualizing the interior of a hollow organ or part (such as the bladder or esophagus) for diagnostic or therapeutic purposes that typically has one or more channels to enable passage of instruments (such as forceps or scissors).
The Greek prefix endo- means "within, inside", so around 1860 an early crude instrument for looking deep inside the body was named the endoscope. But modern endoscopy required the invention of the electric lightbulb and then fiber-optic cable, so the first modern endoscopes date only to 1967. An endoscope may be inserted through a natural passageway (for example, through the nose or down the esophagus) or through a tiny cut in the skin. A tiny camera with a light at the end of the cable sends back images onto a screen, and the surgeon uses special instruments that work through a tube alongside the cable. There are now specialized types of endoscopes for every part of the body, where they can take tissue samples, cut out small growths, or remove foreign objects.