Decoding Medical & Science Terms: Roots, Prefixes & Suffixes
Break a long medical word into its parts and its meaning falls out, even if you have never seen the word before.
Medical and science words look intimidating, but most are built from a small set of Greek and Latin parts. Learn the parts and you can decode a word you have never seen: 'electrocardiogram' is just electro (electrical) + cardi/o (heart) + gram (record). Doctors, nurses, lab scientists, and pharmacists rely on this every day, because the same roots reappear across thousands of terms. This is the highest-leverage vocabulary skill in the pathway: instead of memorizing every word, you learn the pieces once. Use the illustrated Word Parts tab of the glossary as your reference while you practice.
- Common Core · L.9-10.4.bIdentify and correctly use patterns of word changes; use Greek and Latin affixes and roots as clues to a word's meaning.
- Common Core · RST.9-10.4Determine the meaning of domain-specific words and phrases in a science or technical text.
- Ohio · Ohio ELA L.9-10.4Use roots, prefixes, and suffixes to determine the meaning of unknown words.
- NGSS · SEP-8Obtaining, Evaluating, and Communicating Information: read and interpret technical vocabulary in scientific text.
- Hear the parts of a spoken word: Students break a word into chunks before analyzing meaning.
- Look a term up in a reference: Decoding pairs with checking the Word Parts glossary tab.
Prerequisites are inferred: pending teacher review.
Re-learn the skill with worked practice and clear examples.
Decode a full term by splitting it into prefix + root + suffix, giving each part its meaning, then reading them together. Practice on real medical words using the meanings from the Word Parts glossary tab.
Use the parts (hepat = liver, -itis = inflammation). What does 'hepatitis' mean?
Reviewed| Part | Meaning |
|---|---|
| hepat | liver |
| -itis | inflammation |
- A.A liver transplant
- B.Inflammation of the liver
- C.Removal of the liver
- D.A record of the liver
Show the worked solution ▾
Answer: B. Inflammation of the liver
- Step 1: Assign meanings: hepat = liver; -itis = inflammation.
- Step 2: Combine: Read as inflammation of the liver.
Why it's right: hepat (liver) + -itis (inflammation) means inflammation of the liver.
- A: No part here means transplant.
- C: Removal would be the suffix -ectomy, not -itis.
- D: A record would be the suffix -gram, not -itis.
Aligned to Common Core RST.9-10.4: decode domain vocabulary · reading level ~grade 9
The suffix '-ectomy' means 'surgical removal.' What is an 'appendectomy'?
Reviewed- A.Inflammation of the appendix
- B.Surgical removal of the appendix
- C.A picture of the appendix
- D.The study of the appendix
Show the worked solution ▾
Answer: B. Surgical removal of the appendix
- Step 1: Read the suffix: -ectomy means surgical removal.
- Step 2: Combine with the root: append (appendix) + ectomy (removal) = removal of the appendix.
Why it's right: -ectomy means surgical removal, so appendectomy is surgical removal of the appendix.
- A: That would use -itis.
- C: That would use -gram.
- D: That would use -ology.
Aligned to Common Core L.9-10.4.b: suffixes · reading level ~grade 9
Break down 'bradycardia' using brady- (slow) and cardi/o (heart). What does it mean?
Reviewed- A.A fast heart rate
- B.A slow heart rate
- C.An enlarged heart
- D.Inflammation of the heart
Show the worked solution ▾
Answer: B. A slow heart rate
- Step 1: Assign meanings: brady- = slow; cardi/o = heart; -ia = a condition.
- Step 2: Combine: A condition of a slow heart, that is a slow heart rate.
Why it's right: brady- (slow) + cardi/o (heart) means a slow heart rate.
- A: Fast would be the prefix tachy-.
- C: Enlarged is not indicated by these parts.
- D: Inflammation would use -itis (carditis).
Aligned to Common Core RST.9-10.4: decode with prefix + root · reading level ~grade 9
- A student decodes a lab report term by splitting it into parts instead of guessing.
- A test-taker meets an unfamiliar word and builds its meaning from a known prefix and root.
- A group builds a word wall of terms grouped by shared root.
Fill these in as you work through the lesson.
- Root (core meaning, usually a body part):
- Prefix (front; changes the meaning):
- Suffix (end; names a condition or action):
- Combining vowel (usually 'o'; links parts):
To decode a term, split it into , , and , give each part its meaning, then read the first and the root next.
- Split 'gastritis' into its parts and give each part a meaning.
- What does the prefix hyper- add to a word? Give one example.
- Build a word that means 'the study of the heart' from its parts.
Decode 'neuritis' using neur/o (nerve) and -itis (inflammation): neur means ____, -itis means ____, so neuritis means ____.
The vocabulary of this topic, shown in the way you will meet it.