Medical Terminology Daily (MTD) is a blog sponsored by Clinical Anatomy Associates, Inc. as a service to the medical community, medical students, and the medical industry. We will post a workweek daily medical or surgical term, its meaning and usage, as well as biographical notes on anatomists, surgeons, and researchers through the ages. Be warned that some of the images used depict human anatomical specimens.

Click on the link below to subscribe to the MTD newsletter. If you think an article could be interesting to somebody else, click on the mail link at the top of each article to forward it. 

You are welcome to submit questions and suggestions using our "Contact Us" form. The information on this blog follows the terms on our "Privacy and Security Statement"  and cannot be construed as medical guidance or instructions for treatment. 

We have 159 guests online

A Moment in History

Antoine Louis

French surgeon, anatomist, and physiologist. Following his medical studies and a long career as a physiologist, Antoine Louis was named Permanent Secretary of the Royal French Academy of Surgery. His other titles were those of Professor of the Royal Academy, Consultant Surgeon of the Armies of the King, member of the Royal Society of Sciences of Montpellier, Inspector of the Royal Military Hospitals, and Doctor in Law of the University of Paris. As a member of these academies Louis was instrumental in the design and construction of the guillotine. Initially called the "Louisette", this device was later named after another French physician in the same committee, Dr. Joseph-Ignace Guillotin.

Antoine Louis' name is better know to history as the eponymic origin of the "sternal angle" also know as the "Angle of Louis" and synonymously (probably by misspelling or translation) the "angle of Lewis", and "angle of Ludwig". This anatomical landmark is extremely important as it serves as a superficial landmark for important anatomical occurrences (click here).

As a point of controversy, there are some that contest the history of this eponym adjudicating it to Pierre Charles Alexander Louis (1787-1872), another French physician dedicated to the study of tuberculosis.

1. Srickland, N; Strickland A Angle of Louis, More Than Meets the Eye. MedTalks:
2. Ramana, R. K., Sanagala, T. and Lichtenberg, R. (2006), A New Angle on the Angle of Louis. Congestive Heart Failure, 12: 197–199
. "The origin of Medical Terms" Skinner, HA; 1970

 "Clinical Anatomy Associates, Inc., and the contributors of "Medical Terminology Daily" wish to thank all individuals who donate their bodies and tissues for the advancement of education and research”.

Click here for more information

abebooks banner


Medical terminology suffixes are sometimes formed by several components. The suffix component [-y] means "process" and can be used in many different ways.

A "process" can be an actual bony outcropping, a structure, or it can be an action or a series of actions.

Let's dissect a few suffixes to analyze their construction:

• [-(o)tomy]: This suffix is composed by [-tom-], derived from the Greek word [τομή] meaning "to incise" or "to cut". By adding the suffix component [-y] we obtain the meaning of "process of cutting".

• [-ectomy]: This suffix is more complicated. It originates from two Greek root terms [εκτός] (ectos) meaning "out or outside" and "[tomos], which means "to cut" or "to open".  By adding the suffix component [-y] we obtain the meaning of "process of cutting out". Other synonyms are: extirpation, excision, and removal.

• [-(o)logy]: The accepted meaning of this suffix is "study of", although a better meaning would be "process or action of studying". This suffix has an interesting evolution that you can read here.

The suffix [-y] can also be used alone, as in the case of the anatomical term mesentery. This term is of Greek origin. The prefix [mes(o)-] means "middle", the root term [-enter-] means "small intestine" or "intestine", and the suffix [-y] means "process" or "structure". Thus, the mesentery is "a structure in the middle".