It is now time to move on to discuss the Greek and Latin roots of the infrastructure of the central and peripheral nervous system:
Neuron—sinew, tendon, nerve {neuro-}
Nervus (Lat.)—sinew, nerve, vigor, determination
Let's take a look at the Latin root first. A nerve, derived from the Latin root nervus: sinew, nerve, indeed is etymologically a sinew or tendon along which electrochemical impulses travel that allows coordination and communication within the body, the core of which is the central nervous system, composed of the largest mass of nerves, the cerebrum, and the spinal cord. These nervous (of or pertaining to a nerve) cables, as it were, are comprised of neurons (technically the peripheral axons), and are only part of the peripheral nervous system, not the central nervous system, where the nerves are known as tracts. The body is able to communicate with itself via this highly complex coordinate system via electrochemical impulses which move along the axons, much as a house or computer is wired to allow electricity to flow through it.
One can be said to be nervous when one feels apprehensive, shaky, or agitated due to imminent expectation (nervosity is the state of being nervous); when one's nerves completely get the better of one, a person can head for what is popularly known as a nervous breakdown, a severe emotional collapse that may or may not be caused directly by the nerves; it is interesting to note that this parlance is purely social in usage, and is not recognized by the medical or scientific community. The optic nerve links the retina (via the Latin root rete—net; the retina is a net made of rods and cones that catches photons, related to reticulated python and reticulated giraffe, both of which have a netlike pattern on their epidermis) to the brain, where images that the eye receives are processed and turned into the images that we "see." The auditory nerve links the ears with the brain, where sounds are processed, the olfactory nerve from the mucus membranes of the nose to the cerebrum.
If one is enervated, one has lost energy or "vigor": The hiker was so enervated by his arduous ascent up Mauna Kea that he felt as if all his ‘nerves’ had been taken ‘out,’ leaving him limp as a warm cherry Knox Block. A situation can be unnerving if one feels totally out of one's element and experiences clear and present danger, hence being deprived of one's courage or chutzpah or fortitude.
In regards to pure medical anatomy, the Greek root neuron is much more frequently in use. Neurons, also known as nerve cells, not only consitute nerves, but also are the electrochemical cells that comprise the central nervous system (brain and spinal column) and nerves; each neuron possesses a single axon (the primary transmission lines that allow communication between neurons) and one or more dendrites (via the Greek root dendron: tree; witness dendrochronology, the determining of the age of a tree by counting its rings).
Neural, surprisingly enough, refers to a nerve (again, a bundle of neurons) or the nervous system, whereas the word neuronal or neuronic refers to individual neurons themselves. Neuralgia is severe and sharp pain that exists within a nerve or bundle of nerves (consider the Greek root algos: pain; it gives us such words as analgesic: a medicine that takes "pain away;" nostalgia the "pain of home;" and odontalgia, a "toothache."). Neuritis is inflammation of a nerve, which can cause such symptomatology as severe pain, muscle atrophy, and loss of reflexes {note that the Greek suffix -itis, inflammation, is used ubiquitously in such words as tonsillitis, mastitis (inflammation of the breast), laryngitis (of the larynx), tendonitis (most commonly of the Achilles tendon), and nephritis (of the kidney)}.
What sounds more euphonic to you, a nervologist or a neurologist? Nervology or neurology? The Greek root certainly has much more cachet, and is coupled with a Greek suffix (logos—word, speech, study, saying, reason, thought, calculation, ratio, a progenitor of thousands of different disciplines, such as biology, psychology, limnology, eschatology, etc. etc.); it is considered linguistically gauche to mix Latin with Greek roots, although it is done often.
My next article in this series will focus on the study of neurology and the disciplines that neurologists, or those physicians that study the nervous system and its related ailments (neuropathology) specialize in.
Much of the information in the above article was derived from the vocabulary enhancing web site http://www.wordempire.com the site to increase English vocabulary proficiency.
Brett Brunner has been teaching Latin and English vocabulary in college-prep schools for seventeen years, as well as summer courses targeting the verbal section of the SAT. He spent eleven years at Saint Mary’s Hall in San Antonio, TX, where he presided as the chair of the Language Department, overseeing the Spanish, Japanese, French, and Latin programs; in addition, he taught Latin, etymology, philosophy, and world history. He designed a course in Greek and Latin roots to build vocabulary in the mid 90s, from which he had the idea of creating his own comprehensive Greek and Latin roots textbook, Word Empire, which is now used by numerous schools and individuals, and includes distribution through the American Classical League. He spent the academic year of 2000-2001 on sabbatical, finishing Word Empire, and recently completed Word Empire III: Clarity; he also wrote a book on teaching methodology, entitled Chaos Motivation, which describes his unique, infrastructural motivational methodology--he finished the second edition of Chaos Motivation in the fall of 2006. He holds an undergraduate honors degree from UW Madison, and an M.A. in English from the University of Virginia; he has continued his studies in Latin at the University of Georgia at Athens. He was awarded the prestigious Master Teacher's award at Saint Mary's Hall in the fall of 2003 for his success in motivating students at the middle and upper-school levels. In June of 2005, Mr. Brunner was named Teen Ink’s Educator of the Year. Mr. Brunner regularly presents his learning English vocabulary methodology at conferences, the most recent being at Vanderbilt University for the American Classical League. He currently teaches Latin at Tandem Friends School in Charlottesville, VA, where he writes a Latin roots SAT word of the day column on the school's web site, and also frequently contributes to his Greek and Latin roots blog.