Academics at University Hospital Limerick in Ireland have classified a new human organ, called the the mesentery.
They made the discovery by using complex microscopy.
The mesentery was first thought to be made up of separate structures, but has now been proven to be an independent organ.
It is a fold of the peritoneum membrane which attaches the stomach, small intestine, pancreas and other organs to the abdomen.
Scientists are hopeful that the discovery will aid the research and understanding of abdominal and digestive diseases.
Professor Calvin Coffey, who made the discovery, said: “We are now saying we have an organ in the body which hasn’t been acknowledged as such to date.
“The anatomic description that had been laid down over 100 years of anatomy was incorrect. This organ is far from fragmented and complex. It is simply one continuous structure.”
Gray’s Anatomy, one of the most widely-used series of medical textbooks in the world, will now be updated accordingly, reports the Daily Mail.
Professor Coffey added: “This affects all of us. Up to now there was no such field as mesenteric science. Now we have established anatomy and the structure.
“The next step is the function… you can identify abnormal function, and then you have disease. Put them all together and you have the basis for a whole new area of science.”