Basic Medical Terminology - O (Part 1) Quiz

Answer: back of the head

Occiput is a Latin word which means "the back of the head" and refers to the region of the back and lower part of the skull. It is derived from "ob" meaning against or behind, and "caput" meaning head (no relation to the word "kaput", meaning broken down, wrecked or useless, which is of German origin).

The anatomical structures found in that vicinity are described using the adjective occipital - e.g. the occipital bone, the occipital lobes (of the brain), and the occipital nerves.

Answer: testis, testicle

These word parts all relate to the testicles or testes, from the Greek "orkhis" with the same meaning. The ancient Greeks named things, such as diseases and body parts, after things that they were familiar with - by noting their similarity to plants, animals, colours, shapes, tools, and other things they observed in the world around them. The ancient Greeks noted the similarity between the human testicle and the underground stem or tuber of the orchid plant. Some sources say the testicle was named after the orchid and other sources say the orchid was named after the testicle. Like the chicken and the egg, we'll probably never know which came first - but I am sure you'll never look at orchids the same way again.

Examples of usage include medical terms such as orchidectomy (surgical removal of the testis or testes), orchiopexy (surgical fixation of an undescended testis in the scrotum), and orchitis (infection/inflammation of a testis).

Answer: tooth

The Greek words "odon" and "odontos" mean "tooth". Orthodontics is the area of dentistry which involves straightening teeth, typically with braces. Periodontics involves the structures which surround the teeth, primarily the gums (peri- means around or enclosing). Endodontics is the area of dentistry dealing with the structures inside the teeth, i.e. the dental pulp, and involves procedures such as root canal work (endo- means within).

A paedodontist is a dentist who specialises in children's teeth (paed- means child).

Answer: like, resembling

The suffix -oid is derived from the Greek "oeides" meaning form. In medical terminology the suffix -oid means like or resembling. In anatomy, many parts of the body end in -oid because the body part is shaped like something. The word part in front of the suffix -oid tells you what it resembles or is shaped like.

For example, the sigmoid colon is so-called because it is S-shaped or like the Greek letter sigma. Other body parts named for their shape include the arachnoid membrane (web-like), the deltoid muscle (the Greek letter delta), the mastoid process (breast), the scaphoid bone (boat) and the thyroid gland (shield).

The disease typhoid was named because it was originally thought to be a variant form of a disease known as typhus (typhoid = like typhus).

Answer: few, deficiency

Olig- and oligo- are prefixes meaning few or deficiency, from the Greek "oligos" meaning few, scanty, or small. Examples of usage include oligospermia (low sperm count), oliguria (the production of small volumes of urine) and oligomenorrhoea (scanty or infrequent menstrual flow).

Answer: tumour

In medical terminology, the suffix -oma is a Greek word element that designates a growth or tumour. Although people tend to equate the term "tumour" with "cancer", tumours can be benign (not cancerous) or malignant (cancerous). Some examples of tumour-related terminology include melanoma, sarcoma, and carcinoma. Tumours are usually named according to the type of cells or tissues involved. For example, sarcomas arise from connective tissue (typically bone, cartilage, fat and nerve tissue). Melanoma literally means "black tumour" and is a type of skin cancer involving the melanin-producing cells.

Most cancers are carcinomas and involve epithelial tissue. The word part carcin/o is derived from the Greek "karkinos" which means both crab and cancer. Ancient Greek physicians used the word to refer to malignant tumours because they observed that the behaviour of a crab was similar to the "behaviour" of a malignant tumour. Just as a crab grabs its prey and does not let go, malignant tumours are also very tenacious as they invade the body's tissues, leading to inevitable death.

Answer: nail(s)

Onych- and onycho/o refer to the fingernails and toenails and are derived from the Greek "onuks" or "onyx" meaning nail. The mineral onyx, a type of quartz, derives its name from the same source. Onyx comes in many colours but a common form is a translucent pink with white streaks which the Ancient Greeks noted was like a human fingernail. It was commonly used in the making of jewellery such as cameos.

Onych- and onych/o are used in medical terms such as onychophagia (biting the nails), onychotillomania (neurotic picking at the nails), onychomycosis (fungal infection of the nails), and onychosis (disease or deformity of the nails).

Answer: ovary

Oophor- and oophor/o are word parts that refer to the ovary. They are derived from the Greek "oophoros" meaning egg-bearing, which in turn is derived from the Greek "oo" meaning egg, and "phoros" bearing. The ovary contains egg cells (oocytes). Oophorectomy is the surgical removal of an ovary.

Answer: vision

Medical terms relating to conditions of vision typically end in -opia and -opsia from the Greek "ops" meaning eye. (Remember the Cyclops from Greek mythology? They were giant one-eyed creatures - cyclops means "round eye"). Some examples of medical conditions relating to vision include myopia (short- sightedness), hyperopia or hypermetropia (long-sightedness), diplopia (double-vision), presbyopia (age-related changes in vision), and achromatopsia (complete colour-blindness).

Answer: straight, correct, normal

The Greek word "orthos" gives us the prefix ortho-, both meaning straight, true, correct, erect and regular. Words utilising ortho- include orthodox, which translates as "the correct opinion", and is used in expressions such as orthodox medicine and orthodox religion.

Other examples are orthodontics (straightening teeth) and orthopaedic (straightening children - literally). The term orthopaedics was coined by a French physician, Nicholas Andry, in 1741 and reflected the fact that this area of medicine originally dealt with children who suffered from bone, particularly spinal, deformities which required straightening.