Medical Terms

By this time in your career, you have probably mastered the basics of medical terminology, which can be confusing, since the same item can have several names.

Having an understanding of some of the more common prefixes and suffixes used in the medical field will help you with both the certification test and your daily communications with the medical staff. Since space is limited, I tried to select some prefixes and suffixes that have caused me problems over the years.

Tricky Prefixes
Ad means toward, ana means up, and apo (aph) means formed from. Cata (cat, cath) means down, as does the prefix de. Dorsa means the upper surface of an appendage; dorsal pertains to the back or posterior part of the human body. Ect(o) is outside. All this instead of saying closer, up, down, back, and out.

Angio and vaso both refer to blood or lymph vessels. An angiogram is a radiograph of a blood vessel taken during angiography, which is the radiographic visualization of a blood vessel following introduction of contrast media and digital subtraction. An angiocardiogram is the film produced by angiocardiography: a study of the heart and cardiac vessels using angiography.

Some soundalikes are brachi(o), referring to the arm, brachy meaning short, and brady meaning slow. Chrom(o), denoting relationship to color, and chron(o), referring to time, are also easy to confuse. Remember that the “y" is often replaced with an “i" in some terms.

Chol(o) denotes relationship to bile. Combining it with cyst(o), meaning sac, cyst, or bladder, and ectomy, meaning excision, creates a cholecystectomy, the removal of the gall bladder. Just to confuse you, chyl(o), chyle, or chyme is the milky fluid produced during digestion. There is no such procedure as a chylocystectomy, but it looks impressive as the various terms are strung together.

Dermis, derma, and dermal all relate to skin. A dermatologist is a specialist that practices dermatology, the study of skin and treatment of the various conditions or diseases of the skin, while a dermatome is the instrument that harvests skin for grafting. Epi means above, upon, or beside, but epidermis is the outer layer of skin.

Hem(o) and hemat(o) both mean blood, but hemi means half, and homo means common or same. Hepatic pertains to the liver, and hyster(o) pertains to the uterus, but hist(o) denotes a relationship to tissue.

Remember that infra means inferior to, beneath, or below; inter means between or among; and intra means within, into, or during. Lip(o) and lipid pertain to fat, but lith(o) denotes relationship to stone or calculi, for example, kidney stones.

Just to illustrate that there are problems with medical terms, consider the prefix myel(o). It can pertain to the spinal cord, as in myeloencephalitis; to a tumor in the bone marrow, myeloma; or to the formation of bone marrow, myelopoiesis. Also do not confuse my(o), which denotes a relationship to muscle, with myx(o), which pertains to mucus.

While narc(o) pertains to stupor, numbness, or deep sleep, necr(o) refers to a dead body, cells, or tissue. Nephr(o) indicates kidneys, and neur(o) pertains to nerves. Watch out for noct and nyct(o), both meaning night. To illustrate their use in a sentence: A person under 3 or over 65 who is not nocturnal (waking up at night) is in danger of nycturia (wetting the bed).

Omni, meaning all, and poly, meaning many, are often mixed up, so you have to be careful with them. Ped(o) and pod(o) both refer to feet, but to confuse you a little more, ped(o) can also refer to children.

Omphal(o) refers to the navel or umbilicus, while ophthalm(o) refers to eyes. Opisth(o) refers to the back, ortho means straight or normal, and osteo refers to bones.

Pan means all; para means beside, near, or resembling; peri means near or around; but pleo means more, excessive, or multiple. Pleur(o) refers to the membrane in the lungs, the side, or to a rib; but pneum(o) refers both to lungs and respiration. While pre means before, pro can mean either before or rudimentary. Don’t confuse proct(o), meaning rectum, with prot(o), first or original. Pseud(o) meaning false, and psych(o), referring to the mind, are easy to mix up.

In Conclusion
Moving on to some of the suffixes that may confuse you, algia refers to pain. Cyt(o) denotes relationship to a cell and cytosis is cellular process. Both tomy and ectomy mean excision, but sect refers to cut and (o)stomy means opening. Esthesia means perception, feeling, or sensation. Iasis refers to an unhealthy condition or state, and ism to state or condition. (O)pathy refers to disease; itis to inflammation.

A confusing set is plasia, referring to development or formation, plasm(o), denoting the constituent substance of cells, and plasty, meaning form or mold in relation to plastic surgery. Another set to easily mix up is stasis and staxis, which are opposites. Stasis means a stoppage or diminution of the flow of body fluid, while staxis means hemorrhage.

So as good biomeds we have to know several languages to do our jobs. We have to master standard English, engineering English, computer English, and medical English. We, as biomeds, often are criticized for our lack of communication skills, but with so many languages to handle, it is difficult for many to effectively communicate.

Review Questions

1)    If ad means toward, ana means up, and ecto means out, what does ectoderm mean?
    a.    skin removal
    b.    the use of a dermatome
    c.    a hole in the skin
    d.    the outer layers of cells in an embryo

2)    Hemostasis means
    a.    stoppage of bleeding
    b.    hemorrhage
    c.    bleeding from the kidney
    d.    clotting time of blood

3)    Pneumothorax means
    a.    air in the lungs
    b.    air in the stomach
    c.    a leak in the chest wall
    d.    air in the pleural cavity, resulting in a collapsed lung.

4) The suffixes tomy and ectomy both mean
    a.    excision or removal
    b.    insertion
    c.    connection
    d.    they are not the same

Answers: 1-d; 2-a; 3-d; 4-a

David Harrington, PhD, is director of staff development and training at Technology in Medicine, in Holliston, Mass.