The case for learning roots
There are roughly 400,000 words in standard English dictionaries. You cannot memorize them all. But about 60–70% of common English words have Latin or Greek roots — and those roots cluster into patterns. Learn the pattern, recognize the word.
This guide covers the roots that pay off most on the ASVAB. Pair it with the Prefixes & Suffixes guide for maximum range.
High-payoff Latin roots
| Root | Meaning | Example words |
|---|---|---|
| port | carry | transport, import, portable |
| rupt | break | disrupt, erupt, corrupt |
| duc/duct | lead | conduct, deduce, introduction |
| scrib/script | write | describe, prescription, manuscript |
| vis/vid | see | visible, vision, evident |
| dict | say | dictate, predict, contradict |
| fac/fact | make/do | factory, manufacture, factor |
| mit/miss | send | transmit, mission, dismiss |
| vert/vers | turn | convert, divert, version |
| cap/cept | take/seize | capture, intercept, accept |
High-payoff Greek roots
| Root | Meaning | Example words |
|---|---|---|
| chron | time | chronological, synchronize |
| bio | life | biology, biography, antibiotic |
| graph | write | paragraph, photograph, autograph |
| phon | sound | telephone, microphone, symphony |
| geo | earth | geography, geology, geothermal |
| psych | mind | psychology, psyche, psychiatric |
| therm | heat | thermometer, thermal, hypothermia |
| scope | view/watch | telescope, microscope, periscope |
How to use roots on test day
When you see an unfamiliar word, do this fast breakdown:
- Can you spot a root? Underline it mentally.
- Is there a prefix that reverses or modifies it?
- Does the suffix tell you part of speech?
Example: circumspect — circum (around) + spect (look). To look around before acting — cautious, careful.
Example: benefactor — bene (good) + fac (make/do) + -or (one who). One who does good — a patron or donor.
You may not get the exact dictionary definition, but you get close enough to eliminate two or three wrong answers. That's all you need.
Four word families to drill first
Vision words — visible, invisible, envision, visual, visualize, vision, revision (all from vis)
Time words — chronic, chronological, synchronize, anachronism, chronicle (all from chron)
Life words — biology, biography, biography, antibiotic, symbiosis (all from bio)
Sound words — telephone, symphony, microphone, phonics, euphony (all from phon)
Learn one family per study session. By the time you sit the test, these roots will fire automatically.