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2.1 Greek and Latin Roots, Prefixes, and Suffixes
CAT-ASVAB Computer Adaptive ASVAB
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1 Chapter 1: CAT-ASVAB Overview, Adaptive Mechanics & Test Strategy
1.1 CAT-ASVAB Architecture, MEPS Administration & Subtest Structure 1.2 Computer Adaptive Testing (CAT), IRT Engine & Pacing Rules 1.3 AFQT Scoring Formula, VE Weighting & Service Branch Minimums 1.4 Military Composite Line Scores & MOS/AFSC/Rating Classification
2 Chapter 2: Word Knowledge (WK)
2.1 Greek and Latin Roots, Prefixes, and Suffixes 2.2 Context Clues, Secondary Meanings, and Nuanced Synonyms 2.3 Military, Technical, and Formal Vocabulary in Context 2.4 High-Frequency Word Bank and the 36-Second Word-Attack Protocol
3 Chapter 3: Paragraph Comprehension (PC)
3.1 Identifying Main Ideas, Central Themes, and Author Purpose 3.2 Supporting Details, Factual Extraction, and Structural Analysis 3.3 Inferences, Contextual Meaning, and Tone Evaluation
4 Chapter 4: Arithmetic Reasoning (AR)
4.1 Translating Complex Word Problems into Algebraic Expressions 4.2 Ratios, Proportions, Rates, and Combined Work Problems 4.3 Percentages, Interest, Profit, and Financial Math 4.4 Applied Geometric Word Problems (Area, Perimeter, Volume)
5 Chapter 5: Mathematics Knowledge (MK)
5.1 Number Properties, Exponents, Radicals, and Polynomials 5.2 Linear Equations, Quadratic Equations, and Inequalities 5.3 Geometric Principles, Coordinate Geometry, and Trigonometry Fundamentals 5.4 Basic Probability, Permutations, Combinations, and Statistics 5.5 Fractions, Rational Expressions, and Non-Calculator Computation
6 Chapter 6: General Science (GS)
6.1 Cellular Biology, Human Anatomy, and Biological Systems 6.2 Chemistry Fundamentals, Atomic Structure, and Reactions 6.3 Classical Physics, Energy, Forces, and Motion 6.4 Earth Science, Meteorology, Astronomy, and Environmental Science 6.5 Scientific Method, Measurement Systems, and Laboratory Instruments
7 Chapter 7: Electronics Information (EI)
7.1 Voltage, Current, Resistance, Ohm's Law, and Power 7.2 Circuit Analysis: Series, Parallel, and Combination Circuits with Kirchhoff's Laws 7.3 Electronic Components, Semiconductor Devices, and Schematic Symbols 7.4 Magnetism, Electromagnetism, Motors, and Generators 7.5 Circuit Protection, Wiring, Measurement Instruments, and Electrical Safety
8 Chapter 8: Auto Information (AI)
8.1 Internal Combustion Engines and the Four-Stroke Cycle 8.2 Powertrain, Transmission, Drivetrain, and Fuel Systems 8.3 Braking Systems, Suspension, Steering, and Electrical Diagnostics
9 Chapter 9: Shop Information (SI)
9.1 Hand Tools, Measuring Instruments, and Cutting Implements 9.2 Power Tools, Fasteners, Hardware, and Joining Techniques 9.3 Woodworking, Metalworking, Materials, and Workshop Safety
10 Chapter 10: Mechanical Comprehension (MC)
10.1 Simple Machines: Levers, Classes, and Mechanical Advantage 10.2 Pulleys, Wheel and Axle Systems, and Inclined Planes 10.3 Gears, Belt and Chain Drives, Cams, and Torque Transmission 10.4 Fluid Power, Hydraulics, Pneumatics, and Buoyancy (Pascal & Archimedes) 10.5 Forces, Friction, Work, Power, Energy Conservation, and Wave Mechanics
11 Chapter 11: Assembling Objects (AO)
11.1 Spatial Relationship Fundamentals & 2D Silhouette Synthesis 11.2 Connection Point Problems, Interior Seams, and Labeled Points 11.3 High-Speed Pacing, Elimination Tactics, and Visual Pattern Recognition
2.1 Greek and Latin Roots, Prefixes, and Suffixes
Key Takeaways Explain This Topic AI
Word Knowledge (WK) accounts for 50% of Verbal Expression (VE), which carries double mathematical weight in the AFQT formula: AFQT = 2VE + AR + MK.
The CAT-ASVAB delivers 15 Word Knowledge questions in 9 minutes (36 seconds per item) utilizing an adaptive Item Response Theory (IRT) engine with no backtracking.
Morphological analysis deconstructs complex vocabulary into prefixes (direction/polarity), base roots (core semantic payload), and suffixes (part of speech/state).
Mastering high-yield Latin and Greek roots (such as -duc-, -tract-, -spec-, -chron-, -loqu-) alongside diagnostic affixes enables rapid elimination of incorrect distractor choices.
Last updated: August 2026
2.1 Greek and Latin Roots, Prefixes, and Suffixes
Core Principle: Word Knowledge (WK) assesses vocabulary breadth and linguistic decoding ability through direct synonyms and contextual usage items. On the Computer Adaptive Test (CAT-ASVAB), examinees face 15 scored questions in 9 minutes —allocating an average of 36 seconds per question , the fastest required pace on the entire battery. Because Word Knowledge combines with Paragraph Comprehension to generate Verbal Expression (VE), and VE carries double weight in the Armed Forces Qualification Test (AFQT) formula ( AFQT = 2 VE + AR + MK \text{AFQT} = 2\text{VE} + \text{AR} + \text{MK} AFQT = 2 VE + AR + MK ), morphological proficiency is the single most leveraged academic skill for maximizing enlistment percentiles and technical line score qualifications.
1. The Strategic Architecture of Word Knowledge in AFQT & Line Scoring
The Armed Forces Qualification Test (AFQT) percentile score governs military enlistment qualification across all service branches (the Army, Marine Corps, and Air Force each publish 31 for diploma holders and the Coast Guard publishes 32; the Navy and Space Force publish no numeric floor) and determines eligibility for enlistment bonuses. The Department of Defense computes the raw AFQT composite score using the following standard equation: AFQT Raw Score = 2 VE + AR + MK \text{AFQT Raw Score} = 2\text{VE} + \text{AR} + \text{MK} AFQT Raw Score = 2 VE + AR + MK
Where Verbal Expression (VE) is derived directly from the candidate's scaled scores in Word Knowledge (WK) and Paragraph Comprehension (PC) : VE = WK + PC \text{VE} = \text{WK} + \text{PC} VE = WK + PC
Every scaled score point gained in Verbal Expression delivers two times the mathematical impact on your AFQT total compared to a point earned in Arithmetic Reasoning (AR) or Mathematics Knowledge (MK). Furthermore, Word Knowledge is an indispensable component of service composite line scores:
General Technical (GT = VE + AR): Required for Army Special Forces (110+), Warrant Officer Flight Training (110+), and Military Intelligence.
Skilled Technical (ST = GS + VE + MK + MC): Required for Navy Nuclear, Cyber Warfare, and Electronics Maintenance ratings.
Clerical (CL = VE + AR + MK): Required for administrative, legal, personnel, and logistics specialties.
CAT-ASVAB Item Response Theory & Pacing Dynamics
The CAT-ASVAB administers Word Knowledge adaptively via Item Response Theory (IRT):
Item Count & Timing: 15 scored items in 9 minutes (36 seconds per question). If your session draws unscored tryout items in Word Knowledge the limit rises to 18 minutes, but the per-item pace stays the same.
Sequential Commitment: Backtracking, item skipping, and answer modification are strictly prohibited .
Early-Item Weighting: The IRT engine initiates testing with an ability estimate of θ = 0.0 \theta = 0.0 θ = 0.0 . Early correct responses rapidly drive the algorithm into high-difficulty item pools ( b > + 1.0 b > +1.0 b > + 1.0 ), unlocking scaled scores above 60. Careless errors on early items depress θ \theta θ , requiring multiple subsequent correct answers simply to regain average baseline standing.
Morphological Decoding: Brute-force memorization of thousands of dictionary definitions is inefficient. Mastering morphology—the structural study of morphemes (prefixes, roots, suffixes)—empowers you to deconstruct and decode multisyllabic words rapidly under time constraints.
2. Morphological Structure: Prefixes, Roots, and Suffixes
Over 60% of English vocabulary—and greater than 90% of formal, technical, and military terminology on the ASVAB—is assembled from classical Greek and Latin morphemes. A word's semantic architecture consists of three potential building blocks: +-----------------------------------------------------------------------------------------+
- | MORPHOLOGICAL ARCHITECTURE |
- +-----------------------------------+---------------------------------+-------------------+
- | 1. PREFIX | 2. ROOT (BASE MORPHEME) | 3. SUFFIX |
- | Positioned BEFORE the root | Core semantic payload | Positioned AFTER |
- | Modifies direction, time, | Establishes central concept | Designates part |
- | quantity, or polarity | or action | of speech & state |
- | (e.g., circum- = around) | (e.g., spec / spic = look/see) | (e.g., -ous = full)|
- +-----------------------------------+---------------------------------+-------------------+
- | SYNTHESIS: CIRCUM + SPEC + OUS = "looking around carefully in all directions" |
- | -> DEFINITION: Cautious, prudent, vigilant, discreet |
- +-----------------------------------------------------------------------------------------+
Prefix (Affix before root): Redirects the semantic trajectory, establishes temporal or spatial orientation, or inverts polarity (e.g., ante- , sub- , contra- ).
Root (Base morpheme): Supplies the foundational conceptual meaning (e.g., tract , belli , chron ).
Suffix (Affix after root): Establishes the grammatical category (noun, verb, adjective, adverb) and denotes a condition, degree, or state of being (e.g., -tion , -ify , -able ).
3. High-Yield Greek & Latin Roots Reference Catalog
The following 24 high-yield roots appear with regular frequency across CAT-ASVAB Word Knowledge items. Memorize their core concepts and study their derivatives:
Root Morpheme Linguistic Origin Core Conceptual Meaning High-Yield Examples & Definitions
duc / duct Latin ( ducere ) Lead, pull, guide Induce (lead into/persuade); Deduce (lead down from premise/infer); Ductile (easily guided/drawn out)
tract Latin ( trahere ) Pull, drag, draw Intractable (stubborn/hard to pull); Protracted (drawn out/prolonged); Retract (pull back)
spec / spic Latin ( specere ) Look, see, observe Circumspect (cautious/looking around); Conspicuous (easily seen); Retrospect (looking backward)
chron Greek ( chronos ) Time Anachronism (temporal misplacement); Chronic (persisting over time); Synchronize (align in time)
loqu / loc Latin ( loqui ) Speak, talk Loquacious (excessively talkative); Eloquent (fluent in speech); Circumlocution (roundabout speech)
belli Latin ( bellum ) War, hostility, fight Belligerent (hostile/warlike); Bellicose (eager to fight); Rebellion (armed uprising against rule)
cred Latin ( credere ) Believe, trust Credulous (too trusting/gullible); Incredulity (skepticism); Creed (system of formal beliefs)
path Greek ( pathos ) Feeling, suffering, disease Antipathy (deep hatred/hostility); Apathy (lack of feeling/concern); Pathology (study of disease)
corp Latin ( corpus ) Body Corporeal (bodily/physical); Incorporate (unite into one body); Corpulent (excessively bulky/fat)
vert / vers Latin ( vertere ) Turn, change direction Subversive (turning from beneath/undermining); Adversary (opponent turned against); Avert (turn away)
dict Latin ( dicere ) Speak, say, declare Edict (authoritative public proclamation); Contradict (speak against); Malediction (curse/bad speech)
gen Greek ( genos ) Birth, origin, kind Engender (bring into existence); Congenital (existing from birth); Progeny (offspring/descendants)
jur / jud Latin ( jus / judex ) Law, justice, swear oath Judicious (showing sound judgment); Abjure (solemnly renounce under oath); Perjury (lying under oath)
phil Greek ( philos ) Love, affinity, attraction Philanthropy (charitable love for humankind); Bibliophile (book lover); Philosophy (love of wisdom)
phon Greek ( phone ) Sound, voice Cacophony (harsh, jarring discord); Euphony (pleasing sound); Phonetic (relating to speech sounds)
vid / vis Latin ( videre ) See, perceive, look Provident (seeing ahead/frugal); Invidious (causing ill will/envious); Envision (picture mentally)
auto Greek ( autos ) Self, same Autonomous (self-governing/independent); Autocrat (absolute sole ruler); Automaton (self-operating device)
bio Greek ( bios ) Life, living organism Symbiosis (living together in mutual benefit); Biosphere (global life zone); Biopsy (tissue exam)
cogn Latin ( cognoscere ) Know, learn, understand Cognizant (fully aware/conscious); Incognito (identity disguised); Recognize (identify from prior knowledge)
flu / flux Latin ( fluere ) Flow, glide Superfluous (overflowing/unnecessary); Fluctuate (shift up and down); Influx (inward flow)
bene / bon Latin ( bene ) Good, well Benefactor (one who gives financial aid); Benevolent (kind-hearted); Benign (gentle/harmless)
mal Latin ( malus ) Bad, evil, ill, wrongful Malfeasance (official misconduct); Malevolent (wishing harm); Maladroit (clumsy/awkward)
omni Latin ( omnis ) All, whole, everywhere Omnipotent (all-powerful); Omniscient (all-knowing); Omnipresent (present everywhere)
voc / vok Latin ( vocare ) Call, voice, summon Equivocate (speak ambiguously); Revoke (call back/rescind); Vociferous (shouting loudly)
4. Master Prefix Taxonomy by Semantic Function
Prefixes alter the trajectory of a root word. Recognizing prefix families enables instant identification of directional movement, spatial positioning, time horizons, and polarity reversals.
Prefix Family Semantic Function Core Definition High-Yield ASVAB Examples
ante- / pre- Temporal / Priority Before, prior to, in front of Antecedent (preceding event); Prerequisite (required beforehand); Precursor (forerunner)
post- / retro- Temporal / Spatial After, behind, backward Posthumous (occurring after death); Retrospective (looking backward at past); Posterity (future generations)
anti- / contra- Polarity / Opposition Against, opposite, counter to Antithesis (direct opposite); Contravene (go against/violate); Antidote (remedy against poison)
dis- / mis- Negation / Error Apart, away, wrongly, falsely Disparate (distinct/apart in kind); Misconstrue (interpret wrongly); Dissent (differ in opinion)
in- / im- / il- Negation / Polarity Not, without, un- (or into) Incessant (unceasing/not stopping); Immutable (unchangeable); Illicit (not permitted by law)
circum- / peri- Spatial / Perimeter Around, roundabout, surrounding Circumnavigate (sail around); Perimeter (outer boundary); Circumscribe (draw limits around)
epi- / super- Spatial / Degree Upon, over, above, excessive Epicenter (point directly above focus); Superfluous (overflowing/excess); Epidermis (outer layer)
hypo- / sub- Spatial / Degree Under, below, beneath, deficient Hypothermia (subnormal temperature); Subjugate (conquer/bring under); Subservient (submissive)
inter- / intra- Spatial / Relational Between/among vs. Within/inside Intermittent (periodic between intervals); Intramural (within institution); Intercede (mediate between)
syn- / sym- Relational / Union Together, with, at the same time Synthesis (combining together); Symbiotic (living together mutually); Synchronous (coinciding in time)
trans- / dia- Movement / Direction Across, through, beyond Transgress (step across/violate boundary); Transient (passing quickly through); Diameter (measure across)
ambi- / amphi- Degree / Polarity Both, around, on two sides Ambiguous (open to multiple interpretations); Ambivalent (conflicting feelings); Amphibious (land and water)
5. Diagnostic Suffixes & Part-of-Speech Indicators
Suffixes indicate the grammatical part of speech and functional state of the term. On CAT-ASVAB items, recognizing the suffix immediately narrows the answer choices by eliminating grammatically incompatible distractors:
Suffix Morpheme Part of Speech Functional Meaning Diagnostic Exam Examples
-able / -ible Adjective Capable of being, worthy of Feasible (capable of being executed); Plausible (credible); Tangible (palpable/touchable)
-acious Adjective Full of, characterized by Voracious (insatiably hungry); Audacious (daring/bold); Tenacious (holding fast/persistent)
-acity Noun Quality, condition, or property Tenacity (persistent determination); Audacity (boldness); Capacity (volume or capability)
-cide Noun Act of killing or destroying Regicide (killing a monarch); Insecticide (pesticide); Homicide (unlawful killing)
-ic / -ical Adjective Pertaining to, characterized by Pragmatic (pertaining to practical action); Lethargic (sluggish); Stoic (unemotional)
-ify / -fy Verb To make, render, or cause to be Pacify (to make peaceful); Fortify (to strengthen); Nullify (to render legally invalid)
-ity Noun State, condition, or abstract quality Austerity (state of severe simplicity); Brevity (conciseness); Adversity (hardship/misfortune)
-logy Noun Science, systematic study of Etymology (study of word origins); Physiology (study of bodily functions); Pathology (disease study)
-ment Noun Concrete result, act, or process Curtailment (act of cutting short); Deployment (positioning forces); Impediment (obstacle)
-ous / -ose Adjective Full of, possessing qualities of Deleterious (harmful/toxic); Bellicose (warlike/aggressive); Luminous (radiating light)
-tion / -sion Noun Action, process, or resulting state Repudiation (act of disowning/rejecting); Diversion (distraction); Cohesion (state of sticking)
-phobia Noun Irrational fear, extreme aversion Claustrophobia (fear of enclosed spaces); Xenophobia (fear of foreigners); Hydrophobia (fear of water)
6. The 4-Step Morphological Deconstruction Method
When encountering an unfamiliar or intimidating multisyllabic vocabulary word on the CAT-ASVAB, execute this standardized four-step deconstruction algorithm:
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- Worked Morphological Deconstructions
- Example A: Equivocate
Step 1 (Prefix/Root 1): equi- = equal, even, same.
Step 2 (Root 2): voc / vocare = call, voice, speak.
Step 3 (Suffix): -ate = verb former (to make, do, or perform).
Step 4 (Synthesis): To speak with "equal voices" or two balanced, ambiguous meanings to deliberately conceal truth → \rightarrow → To use vague or deceptive language to avoid committing .
Example B: Anachronism
Step 1 (Prefix): ana- = against, back, backward, contrary.
Step 2 (Root): chron = time.
Step 3 (Suffix): -ism = noun former (condition, practice, or state).
Step 4 (Synthesis): Something positioned "against time" or out of its proper historical era → \rightarrow → A chronological misplacement or historical inconsistency .
Example C: Intractable
Step 1 (Prefix): in- = not (negative polarity).
Step 2 (Root): tract = pull, drag, draw, guide.
Step 3 (Suffix): -able = adjective former (capable of being).
Step 4 (Synthesis): Not capable of being easily pulled, led, or managed → \rightarrow → Stubborn, obstinate, unyielding, or difficult to solve .
7. High-Yield Morphological Distractor Traps
ASVAB psychometricians engineer distractors to exploit superficial phonetic associations. Watch for these recurring trap archetypes:
The False Cognate / Sound-Alike Trap: Test writers insert words that share auditory or spelling patterns with the prompt but originate from completely distinct roots (e.g., matching candid to candy/sweet , or ingenuous [naive] to ingenious [brilliant]).
The Overly Literal Prefix Trap: Selecting a choice that relies on a physical, literal interpretation of the prefix rather than the word's actual figurative meaning (e.g., defining circumspect as traveling in a circle rather than cautious ).
The Polarity Inversion Trap: Inserting the exact direct antonym to catch candidates who recognize the semantic field but rush past the negative prefix (e.g., pairing immutable with frequently changing ).