Medical Terminology: Suffixes and Plural Formation

Chapter 3: Suffixes in Medical Terminology

Introduction to Suffixes

Suffixes are essential components of medical terms, modifying the meaning of the root word to indicate procedures, conditions, specialties, or instruments. Understanding how suffixes are used and how they affect word formation is crucial for mastering medical terminology.

• Suffix Meaning: The meaning of a suffix itself does not change, but it alters the meaning of the word to which it is attached.

• Word Endings: Every medical term has an ending, which is either a suffix or a complete word.

• Grammatical Role: Suffixes can make a word a noun or an adjective.

Rules for Attaching Suffixes

Proper attachment of suffixes to word roots is governed by specific rules, especially regarding the use of combining vowels.

• Suffix Begins with a Consonant: A combining vowel (usually 'o') is needed to connect the word root and the suffix.

• Example: cephalodynia (head pain)

  • Root: cephal

  • Combining vowel: o

  • Suffix: dynia (begins with consonant)

• Suffix Begins with a Vowel: No combining vowel is needed.

• Example: cephalalgia (head pain)

  • Root: cephal

  • Suffix: algia (begins with vowel)

Application Example

• Question: To combine the word root lith (stone) and suffix tripsy (crushing), is “lithtripsy” a valid medical term?

• Answer: No. The suffix begins with a consonant and needs a combining vowel. The correct form is lithotripsy.

Order of Defining Medical Terms

When interpreting medical terms, follow this order:

1. Define the suffix first.

2. Define the prefix second (if present).

3. Define the word root(s) last.

Example

• Term: gastroplasty

• Root: gastr (stomach)

• Suffix: plasty (surgical repair)

• Definition: Surgical repair of the stomach.

Suffixes Indicating Specialties, Specialists, and Instruments

• Specialist Suffixes:

  • -ician: Specialist in a field of study (e.g., physician)

  • -logist: One who specializes in the study of (e.g., cardiologist)

  • -iatrist: One who treats (e.g., psychiatrist)

• Instrument Suffixes:

  • -scope: Instrument used to view (e.g., microscope)

  • -meter: Instrument used to measure (e.g., thermometer)

Suffixes Indicating Procedures

• -centesis: Surgical puncture (e.g., amniocentesis)

• -graphy: Process of recording (e.g., angiography)

• -scopy: Process of viewing with a scope (e.g., endoscopy)

• -tomy: Incision into (e.g., tracheotomy)

Forming Plurals in Medical Terminology

Rules for Plural Formation

Medical terms often use Latin or Greek endings, so pluralization follows specific patterns rather than simply adding 's'.

Singular Ending	Plural Ending	Example
-a	-ae	vertebra → vertebrae
-ax	-aces	thorax → thoraces
-is	-es	diagnosis → diagnoses
-ix, -ex, -yx	-ices	appendix → appendices
-on	-a	ganglion → ganglia
-um	-a	bacterium → bacteria
-us	-i	nucleus → nuclei
-ma	-mata	carcinoma → carcinomata

Important Note

• Plural suffixes do not always follow a logical pattern, so memorization is important.

• For example, -ix, -ex, or -yx change to -ices, not simply by adding 's'.

Suffix Bingo Activity

Learning Activity

• Students use a bingo card to reinforce suffix knowledge.

• Each blank is filled with a different suffix.

• Definitions are called out; students cross out the corresponding suffix if present.

• Bingo can be achieved vertically, horizontally, diagonally, or with all four corners.

• To win, students must have correct suffixes and be able to define each one.

Additional info: Mastery of suffixes is foundational for understanding and constructing medical terms, which is essential for communication in healthcare settings.