medical terminology

Components of Medical Terms

  • Medical terms are made up of distinct components, which include the:

Word roots

  • The main part or stem of a word
    • Word root and root word are synonymous.
  • A word root conveys the essential meaning of the word and frequently indicates a body part.
  • Adding a prefix or suffix to the word root creates a term.
    • Changing the prefix or suffix will change the meaning of the term.
  • Examples of some word roots are shown in the table.

Prefixes

  • Appear at the beginning of a word
  • Generally describe location and intensity
  • Give the word root a specific meaning
  • prefixes are frequently found in general language, as well as in medical and scientific terminology.
    • Not all medical terms have prefixes.
  • When a medical word contains a prefix, the meaning of the word is altered.

Suffixes

  • Placed at the end of words
  • A suffix usually indicates a procedure, condition, disease, or part of speech
  • Some common suffixes are listed in the table.

Combining vowels

  • The part of a term that connects a word root to a suffix or other word root
    • In most cases, the combining vowel is an o; however, it may also be an i or an e.
  • A combining vowel is usually used when joining a suffix that begins with a consonant or when joining another word root.
  • The combining vowel helps ease the pronunciation of the term. Without the vowel, the term would be rather difficult to pronounce.

Word-Building Rules

  • The following summarizes the rules covered thus far:
    • The prefix is always at the beginning of a term; however, not all terms will have a prefix.
    • The suffix is always at the end of the term.
    • When a suffix begins with a consonant, a combining vowel is used between the word root and suffix to make pronunciation easier.
    • When a term has more than one word root, a combining vowel must be placed between the two word roots, even if the second root begins with a vowel.

Plural Endings

  • Rules you may encounter when converting terms from singular to plural are:
    • Singular words that end in a change to ae when plural.
      • Example: vertebra becomes vertebrae.
    • Singular words that end in is change to es when plural.
      • Example: diagnosis becomes diagnoses.
    • Singular words that end in ex or ix change to ices.
      • Example: apex becomes apices.
    • Singular words that end in on or um change to a.
      • Examples: ganglion becomes ganglia, ovum becomes ova
    • Singular words that end in us change to i.
      • Example: bronchus becomes bronchi.

Special Word Parts

  • Prefixes are used to indicate:
  • Numbers
  • Several prefixes are used to indicate if a term involves a number such as half, or one, two, or more parts or sides. Common prefixes for numbers are listed in the table.

Colors

Several word roots are used to describe color. The most common include those listed in the table.

Positions/directions

  • Prefixes can also be used to describe a position, direction, or location. The most common include those listed in the table.

Directional Terms

  • Directional terms you need to be familiar with include:

Right and left

  • The terms right and left refer to the patient’s right and left sides, not to your right and left sides.

Superior and inferior

  • The superior part of the body, or any body part, is the portion nearer to the head from a specific reference point.
  • The part nearer to the feet is the inferior portion.
  • These terms are also used to describe the relationship of one structure to another.
    • For example, the knee is superior to the foot and inferior to the pelvis.

Lateral and medial

  • Parts of the body that lie farther from the midline are called lateral (outer) structures.
  • The parts that lie closer to the midline are called medial (inner) structures.
  • In general terms, lateral means side.
  • Something that occurs on both sides is referred to as bilateral.
  • When describing the location of an injury, the terms medial and lateral help pinpoint an exact location.
    • For example, the patient has a 2-inch (5-cm) laceration on the medial aspect of the thigh (toward the inside).

Proximal and distal

  • The terms proximal and distal are used to describe the relationship of any two structures on an extremity.
  • Proximal describes structures that are closer to the trunk.
  • Distal describes structures that are farther from the trunk or nearer to the free end of the extremity.
    • For example, the elbow is distal to the shoulder and proximal to the wrist and hand.

Superficial and deep

  • Superficial means closer to or on the skin.
  • Deep means farther inside the body or tissue and away from the skin.
    • For example:
      • A superficial burn involves only the top layer of skin, similar to sunburn.
      • An abrasion is a superficial wound, similar to scraping your knee.
      • A deep laceration involves a cut deeper into the tissue such as with a knife.

Ventral and dorsal

  • Ventral refers to the belly side of the body, or the anterior surface of the body.
  • Dorsal refers to the spinal side of the body, or the posterior surface of the body, including the back of the hand.
  • These terms are used less frequently than the terms anterior (the front surface of the body) and posterior (the back surface of the body).
  • An easy way to remember dorsal is to think of the dorsal fin on a dolphin, which is on its back (posterior) side.

Palmar and plantar

  • The front region of the hand is referred to as the palm or palmar surface.
  • The bottom of the foot is referred to as the plantar surface.

Apex

The apex (plural: apices) is the tip of a structure.

    • For example, the apex of the heart is the bottom (inferior portion) of the ventricles in the left side of the chest.

Movement Terms

  • Flexion is the bending of a joint.
  • Extension is the straightening of a joint.
  • Adduction is motion toward the midline.
  • Abduction is motion away from the midline.

Other Directional Terms

  • A body part that appears on both sides of the midline is bilateral.
  • Something that appears on only one side of the body is said to occur unilaterally.
  • The abdominal cavity is divided into quadrants
    • Right upper quadrant
    • Left upper quadrant
    • Right lower quadrant
    • Left lower quadrant

Anatomic Positions

  • Directional terms include:

Prone and supine

  • These terms describe the position of a body.
  • The body is in the prone position when lying face down.
  • The body is in the supine position when lying face up.

Fowler position

  • The Fowler position was named after a US surgeon, George R. Fowler, MD, at the end of the 19th century.
  • Dr. Fowler placed his patients in a semireclining position with the head elevated to help them breathe easier and to control the airway.
  • A patient who is sitting upright is said to be in the Fowler position.
  • Some refer to semi-Fowler position as sitting with the back of the stretcher at a 45-degree angle and high-Fowler position as sitting at a 90-degree angle.

Eryth/o denotes the color red

Breaking Terms Apart

  • If the term also contains a prefix, define the suffix, then the prefix, and then the word root.
  • Here are some examples:
    • Nephropathy
      • nephr/o/pathy
      • -pathy (suffix meaning "disease")
      • o (combining form)
      • nephr (word root meaning “kidney”)
      • nephropathy = disease of the kidney
    • dysuria
      • dys/ur/ia
      • -ia (suffix meaning “condition of”)
      • dys- (prefix meaning “difficult, painful, or abnormal”)
      • ur (word root meaning “urine”)
      • dysuria = painful urination (pain when urinating) or difficulty urinating
    • hyperemesis
      • hyper/emesis
      • hyper- (prefix meaning “excessive”)
      • emesis (word root meaning “vomiting”)
      • hyperemesis = excessive vomiting
    • analgesic
      • an/alges/ic
      • -ic (suffix meaning “pertaining to”)
      • an- (prefix meaning “without” or “absence of”)
      • alges (word root meaning “pain”)
      • analgesic = pertaining to no pain

Abbreviations, Acronyms, and Symbols

  • Medical abbreviations, acronyms, and symbols are a type of shorthand used to communicate in the medical world.
  • Use only commonly understood acronyms and abbreviations to minimize misinterpretations and errors.

Abbreviations

  • Abbreviations take the place of words to shorten notes or documentation.
  • When using abbreviations on patient care reports, use only standard, accepted abbreviations to avoid confusion and errors.
  • Before using any abbreviations in your own reports, be familiar with accepted use of abbreviations in your local jurisdiction or service area.
  • In some cases, you pronounce the full word when reading an abbreviation, but sometimes you read the letters one by one (for example, EMS is pronounced “E-M-S”)

Acronyms

  • Acronyms are pronounced:
    • As their own word (for example, SAMPLE history is pronounced like the word sample)
    • In combination with abbreviations (for example, DCAP-BTLS is pronounced “D-cap-B-T-L-S,” and the acronym for Urban Search and Rescue (USAR) is pronounced ū-săr

Symbols

  • Symbols are sometimes used as a shortcut in communication and documentation.
  • As with abbreviations, it is important to use only the symbols that are widely understood and accepted.