[UPDATED] Latin words meaning "oval fossa" or "oval depression". The fossa ovalis is, as it names implies, an oval-shaped depression in the interatrial wall of the right ventricle. (see image, pointer "A"). The fossa ovalis represents in the adult the fetal communication between the right and left atrium allowing for fetal oxygenated blood to bypass the pulmonary circulation and enter the systemic circulation directly. The fossa ovalis is closed upon birth by two opposing membranes, and the higher pressure on the left side of the heart.

The persistence of the communication between the right and left atrium is known as an Atrial Septal Defect (ASD) and will need surgical correction. Some anatomists refer to this depression as the "foramen ovale" and it is surrounded by a well-defined muscular border known as the "limbus fossa ovalis", also known by the eponym "ring or anulus of Vieussens"

For more information: 

• On fetal circulation
• On the fossa ovalis (Gray's Anatomy)
• Image of the fossa ovalis (Gray's Anatomy)

This root term is Greek and means "diaphragm", referring specifically to the respiratory diaphragm. Because of the importance to life of the region that includes the respiratory diaphragm, liver, and heart, Greek and Roman physicians saw this area as the seat of emotions, a concept that later evolved to include mental instability, and mind. So, for them the seat or location of the emotional processes was not in the brain, but in the area of conjunction of liver, heart, and respiratory diaphragm.

In the late 1700's, when Franz J. Gall developed a pseudoscience that looked at protuberances in the cranium as predictors of mental capabilities and mental pathologies, he named it [phrenology], or "study of the mind". In fact, look at the word "frenzy" and you will see a variation of the root [-phren-] in it!

Today we use the root term [-phren-] mostly to denote "respiratory diaphragm", although it can be found in medical words such as [schizophrenia] meaning "mind".

George Papanicolau, MD, PhD (1883 - 1962) Greek physician, cytologyst, physyiologist, and zoologist, Papanicolaou was born on the island of Euboea, Greece. His original Greek name is Georgios Nikolaou Papanikolaou. He initially attended the University of Athens, earning his MD in 1904.

After two years as a conscript in the Army, Papanicolaou continued additional studies in Zoology earning his PhD in 1910, later going back to the army as a physician.

Papanicolaou immigrated to the USA in 1913 with his wife. He took a position at the anatomy department of the Cornell University where over the next 45 years established the field of diagnostic cytology, becoming a Professor Emeritus of Clinical Anatomy.

His studies took him to study the cytological patterns in the internal genitalia of guinea pigs, establishing a “cytological calendar”. This study he continued in humans, where he discovered malignant changes in some of the cells obtained. His study on vaginal smears was published in 1943, starting what today is known as a “Pap smear”, a simple annual study that saves thousands of women from cervical and uterine cancer.

Dr. Papanicolaou died in 1960. His personal motto was “I live to serve life”

This compound term is Latin, from [bifurcus] meaning double-pronged. The prefix [bi-] means "two" or "double", and the root [-furcat- ], derived from the Latin [furca] meaning "a fork". Bifurcation means "to fork into two".

In anatomy the term is used to denote the splitting of a structure into two, such as the "bifurcation of the aorta". A variation of the term is "bifid".

This aorta is the main and largest artery of the systemic portion of the circulatory system. It is one of the great vessels of the heart. It starts at the ventriculoaortic anulus and ends at its bifurcation of the aorta in front of the body of the 4th lumbar vertebra. At this point the aorta is continuous with the left and right common iliac arteries.

The aorta has four segments: ascending aorta, aortic arch, descending or thoracic aorta, and abdominal aorta.  

The etymology of the term [aorta] is not clear. The first reference of this structure is from Aristotle, who uses the word "aorta", although in the same work he refers to it as the "tendinous vein". Adrian Van Der Spigelius (1578 - 1625) mentions that the name aorta was given to the curved sheath of a Macedonian knife which has a pronouncedly curved handle (the aorta has a pronounced curve at the aortic arch). Yet another interpretation comes from the Greek, where a similar word means a "curved shoulder strap".

Sources:
1. "The origin of Medical Terms" Skinner, AH, 1970
2. "Medical Meanings" Haubrich, William S. Am Coll Phys Philadelphia 1997

This term is incorrectly spelled [annulus] in most literature. The proper term [anulus] is a derivative of Latin and means "ring" or "circle". The term anulus was adopted by anatomists worldwide in 1955, with the publication of the Nomina Anatomica (Paris). The plural for for anulus is anuli.

There are many ring-like structures or anuli in the human body:

• anulus inguinalis superficialis: Superficial inguinal ring
• anulus inguinalis profundus: Deep inguinal ring
• anulus fibrosus: Center region of an intervertebral disc
• anulus lymphaticus pharyngis: Pharyngeal lymphoid ring or ring of Waldeyer , etc.

Sources:
1. "The origin of Medical Terms" Skinner, AH, 1970
2. "Terminologia Anatomica: International Anatomical Terminology (FCAT)" Thieme,1998
3. "Gray's Anatomy"38th British Ed. Churchill Livingstone 1995
4. "The Doctor's Dyslexicon" Dirckx, JH;Am J Dermatopathol 2005;27:86–88