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The full list of word parts
This is the reference page: the word parts worth knowing, sorted into small groups by meaning, each with two example words; when one is new to you, learn it together with the part. Learn a group a day. When a new word shows up on the test, one familiar piece is often enough to rule out half the choices.
A word part keeps its meaning from word to word
- transmission
- trans- + miss + -ion
- trans- + miss + the act of
- trans- + sending + the act of
- across + sending + the act of
- the act of sending something across
A word part is a piece of a word that means the same thing in many different words. A prefix goes at the front and changes the meaning. The root is the core idea. A suffix goes at the end and usually tells you the kind of word: a thing, a person, a description or an action. Most of these parts come from Latin, the language of ancient Rome, and from Greek.
This page is the list. The lesson Word parts is the method: how to take a new word apart on the test. Use them together.
Learn every part with two words you know
Do not memorize “spect = look” alone. Memorize it with inspect and spectator. When you forget the part, the familiar words bring it back, and two words are a check that the part really means what you think.
How to solve them
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1
Number prefixes: from one to many
These prefixes count. They show up in shapes, in calendars and in sports. When one of these is really the prefix of the word, the meaning has that number in it. Careful: some words only start with the same letters, like decent or center. And in measurements, centi- and milli- mean a hundredth and a thousandth: a centimeter is one hundredth of a meter.
Number prefixesPart Meaning Two examples uni-, mono- one unicycle, monotone bi-, du- two bicycle, duet tri- three triangle, tripod quad-, quart- four quadruple, quarter pent- five pentagon, pentathlon oct- eight octagon, octopus dec- ten decade, decathlon cent- hundred century, centipede mill-, kilo- thousand millennium, kilogram semi-, hemi- half semicircle, hemisphere multi-, poly- many multicolor, polygon Next step: PrefixesTripodtri- (three) + pod (foot)
a camera stand with three legs
Semiannualsemi- (half) + annu (year) + -al
every half year: twice a year
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Prefixes of direction: not, before, after, where
Most prefixes answer one of three questions. Is it the opposite? When is it? Where is it going? A prefix that means “not” flips the word, so it is the first thing to look for.
Not, against, wrong, wellPart Meaning Two examples un- not unknown, unfair in-, im-, il-, ir- not inactive, irregular non- not nonstop, nonfiction dis- not, apart disagree, disconnect a-, an- without atypical, anonymous anti- against antifreeze, antibiotic contra-, counter- against, opposite contrast, counterclockwise mis- wrongly misplace, misjudge mal- badly malpractice, maltreat bene-, eu- well, good beneficial, eulogy Time: before and afterPart Meaning Two examples pre- before prepay, prehistoric ante- before anteroom, a.m. (ante meridiem) post- after postpone, postgame re- again, back replay, recall retro- backward retro (old-style), retroactive Place and directionPart Meaning Two examples ex-, e- out exit, emit in-, im- in, into include, inject ab- away from absent, abnormal ad-, ac-, at- to, toward adjoin, accept inter- between interstate, interrupt sub- under submarine, subway super-, sur- above, beyond supervise, surpass hyper- / hypo- over / under hyperactive / hypodermic (under the skin) trans- across translate, transatlantic circum- around circumference, circumstance pro- forward progress, promote de- down, away descend, deflate con-, com-, co- together, with connect, cooperate syn-, sym- together, same synonym, sympathy tele- far telephone, telescope Next step: Action rootsIrregularir- (not) + regular
not following the usual pattern
Postponepost- (after) + pon (put)
to put after: move to a later time
Interstateinter- (between) + state
a highway that runs between states
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Roots of action: carry, send, throw, pull, build
These roots are verbs: they name something you do with your body. Many long words are one of these actions plus a prefix that says where the action goes.
Carry, send, throw, pull, leadRoot Meaning Two examples port carry import, porter mit, miss send transmit, mission ject throw reject, projector tract pull, drag tractor, attract pel, puls push, drive propel, expel duc, duct lead conduct, produce Move, turn, build, break, take, holdRoot Meaning Two examples mov, mot move motor, remove ced, ceed, cess go, give way proceed, recess ven, vent come convention, intervene vert, vers turn convert, reverse struct build construct, structure rupt break rupture, erupt cap, capt, cept take, seize capture, intercept tain, ten hold contain, retain grad, gress step, go graduate, progress Next step: See, say, thingsProjectorpro- (forward) + ject (throw) + -or
a machine that throws a picture forward onto a screen
Attractat- (toward) + tract (pull)
to pull toward you
Retainre- (back) + tain (hold)
to hold back: keep
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Roots of seeing, saying and writing, and roots of things
The first group is how people take in and pass on information: see, hear, say, write, know. The second group names things in the world: life, earth, water, heat, the body.
See, hear, say, write, knowRoot Meaning Two examples spec, spect look respect, perspective vid, vis see video, vision aud hear auditorium, audition phon sound phonics, microphone dict say verdict, diction voc, vok voice, call vocal, revoke log, logue word, speech dialogue, monologue scrib, script write describe, manuscript graph, gram write, draw paragraph, diagram cred believe credit, incredible sci know science, conscious path feeling empathy, sympathy Life, earth, water, body, selfRoot Meaning Two examples bio life biography, biodegradable geo, terr earth, land geography, territory hydr, aqua water hydrant, aquarium mar sea marine, submarine therm heat thermometer, thermostat photo, lum light photograph, illuminate chron time chronicle, synchronize meter, metr measure speedometer, symmetry man, manu hand manual, manufacture ped, pod foot pedal, pedestrian corp body corps, corporation pop, dem people population, democracy auto self automatic, autograph Next step: SuffixesAutobiographyauto (self) + bio (life) + graph (write)
the story of your own life, written by you
Thermometertherm (heat) + meter (measure)
a tool that measures heat
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Suffixes tell you the kind of word
A suffix rarely changes the core meaning. It changes the part of speech: whether the word names a thing (a noun), describes something (an adjective), names an action (a verb) or describes how an action is done (an adverb). On the test, the right answer is usually the same kind of word as the question word.
Nouns: a thing, an idea, a personSuffix Meaning Two examples -tion, -sion the act or result of action, decision -ment the act or result of payment, movement -ness the state of being kindness, darkness -ity, -ty the state of being ability, safety -ship, -hood the state or group of leadership, childhood -er, -or a person or thing that driver, inspector -ist, -ian a person who dentist, technician -ee a person who receives employee, trainee Adjectives: describing wordsSuffix Meaning Two examples -able, -ible can be washable, flexible -ful full of helpful, painful -less without useless, homeless -ous full of, having dangerous, famous -ive tending to active, creative -al, -ic related to personal, athletic Verbs and adverbsSuffix Meaning Two examples -ize to make, to become organize, memorize -ify to make simplify, purify -ate to make, to do activate, motivate -en to make widen, strengthen -ly in a way that is quickly, calmly -ward in the direction of backward, upward Next step: CombineThing (noun)act + -ion
action: The action was fast.
Person (noun)act + -or
actor: The actor waved.
Describing (adjective)act + -ive
active: She has an active job.
Action (verb)act + -ive + -ate
activate: Activate your account.
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Putting the parts together, and when they lie
For a long word, work from the end. The suffix says what kind of word it is. The root gives the core idea. The prefix says how that idea changes. Then say the whole meaning in normal English and test it in a sentence.
Word parts are clues, not proof. Some letters only look like a part. Some words have drifted away from their parts over hundreds of years. When the parts give you a strange meaning, trust the sentence and the answer choices.
Next step: Three examples- unpredictable
- un- + pre- + dict + -able
- un- + pre- + dict + able to be
- un- + pre- + said + able to be
- un- + before + said + able to be
- not able to be said before
- cannot be known ahead of time
Suffix first, then root, then prefixes: “The weather in the mountains is unpredictable.” antiqueLooks like anti- (against)
It comes from ante- (before): old
Octoberoct = eight
Yet it is the tenth month: the old Roman year began in March
invaluablein- + value + -able
Not “worthless”: so valuable you cannot put a price on it
reasonStarts with re-
No prefix here: re is just the first two letters
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Three worked examples, from easy to test level
Each one starts with the first try many people make, crossed out, and then the way that works. Read the wrong try too: it is the kind of answer the test puts in the choices.
The test-level one has four choices, like the real test. Find the parts first, then cross out every choice that goes in the wrong direction before you pick.
Example · EasyThe flood submerged the road. What does submerged mean?
First try
Like “merge” on the highway: “joined the road”- Look for a part you know first: sub- means under.
- The root merg means dip or plunge, the same root as “emerge”: to come up out of the water.
- Put them together: plunged under.
- Test it in the sentence: the flood put the road under water. It works.
Answer Covered with water
Example · MediumWhat does inconspicuous mean?
First try
in- = into, so “standing out, easy to spot”- Start at the end: -ous makes an adjective, a describing word.
- The root spic is the same as spec: look, see.
- con- adds force: conspicuous means easy to see, standing out.
- Here in- is in front of a describing word, so it most likely means not: not easy to see. Watch for the few exceptions on this page, like inflammable and invaluable.
- In normal English: hard to notice, blending in.
Answer Hard to notice
Example · Test levelIn the after-action report, the captain listed the antecedents of the delay. Antecedents most nearly means: A) people against it · B) events that came before · C) costs that came after · D) causes of an illness
First try
ante- looks like anti- (against): A) people against it- The suffix -ent makes a noun here: a thing that does something.
- The root ced means go.
- Check the spelling of the prefix: ante-, with an e, means before. Anti-, with an i, means against. So A is out.
- Things that go before: the events that came before the delay. C points the wrong way in time, and D has nothing to do with the parts.
Answer B) events that came before
4 traps in the answer choices
The test writes its wrong answers on purpose: each one is what you get if you make one of these mistakes.
A prefix that is not “not”
Inflammable:
Wrongcannot catch fire
Rightcatches fire easily, the same as flammable
Same letters, different root
Pediatrician:
Wronga foot doctor (ped = foot)
Righta children’s doctor (ped = child, from Greek)
Ignoring the suffix
Solidify:
Wrongsolid, hard
Rightto make solid, to harden (-ify makes a verb)
Look-alike prefixes
Hypothermia:
Wrongtoo much body heat (hyper- = over)
Righttoo little body heat (hypo- = under)
15 questions in three levels
Warm-up first, then core, then test level. Pick an answer, then read why.
On the computer test, Word Knowledge has 15 questions in 9 minutes: about 36 seconds each. On paper it is 35 questions in 11 minutes, about 19 seconds each. There is no time to study a word slowly; you have time to spot one part you know.
Practical tip: look for a part that flips or points the meaning (un-, in-, anti-, mal-, sub-, pre-, post-). Then cross out every choice that goes the other way. Often only one or two choices are left.
On the computer test you cannot go back to a question. If no part helps, pick the choice that fits the sentence best and move on.
The prefix circum- in circumference means:
Show the answer
B. The circumference is the distance around a circle, and circum- means around. Across is trans-, under is sub-, and between is inter-. Circum- means around.
The root ject in reject and projector means:
Show the answer
A. To reject something is to throw it back, and a projector throws a picture onto a screen. Carry is port, pull is tract, and write is scrib. Ject means throw.
Which ending turns the word pure into a verb that means “to make pure”?
Show the answer
D. -ness makes a noun (pureness), -ly makes an adverb (purely), and -ful makes adjectives like helpful. Only -ify means “to make”: purify. The ending is -ify.
The number prefix in decade means:
Show the answer
C. A decade is a period of ten years, and dec- means ten, as in decathlon. Two is bi-, five is pent-, and hundred is cent-. Dec- means ten.
In the word inaccurate, the prefix in- means:
Show the answer
B. In- is in front of a describing word, accurate, so it most likely flips it: inaccurate means not correct. Into is the other meaning of in-, the one in include. Again is re- and before is pre-. Here in- means not.
Using word parts, subterranean most nearly means:
Show the answer
C. sub- means under and terr means earth or land, as in territory. Above would be super-, across would be trans-, and around would be circum-. Subterranean most nearly means under the ground.
Using word parts, transcribe most nearly means:
Show the answer
A. trans- means across or over and scrib means write: to write something over into another form, like turning a recording into text. Speaking is dict, looking is spect, and carrying is port. Transcribe most nearly means to copy in writing.
Using word parts, credible most nearly means:
Show the answer
D. cred means believe, as in credit, and -ible means can be: can be believed. Easy to see mixes it up with vis, well known is a guess from credit, and dishonest adds a “not” that is not there. Credible most nearly means believable.
Using word parts, precede most nearly means:
Show the answer
B. pre- means before and cede means go, as in proceed. To follow after is the opposite, a post- idea. Going around would be circum-, and holding back would be re- plus tain. Precede most nearly means to go before.
Using word parts, dehydrate most nearly means:
Show the answer
C. de- means away, hydr means water, and -ate makes a verb: to take the water away. To add water skips the prefix, to heat up confuses hydr with therm, and to make clean is a guess. Dehydrate most nearly means to remove water.
Circumspect most nearly means:
Show the answer
D. circum- means around and spect means look: someone who looks all around before acting. Careless is the opposite, circular uses only the prefix, and curious looks around for fun, not for safety. Circumspect most nearly means cautious.
The new recruit was told the decision was irrevocable. Irrevocable most nearly means:
Show the answer
A. Work from the end: -able means can be, voc means call, re- means back, and ir- means not. Not able to be called back. Easy to say aloud and loud and clear use only voc, and not yet decided is a guess that ignores both re- and voc: the sentence says the decision was already made. Irrevocable most nearly means cannot be changed.
Benediction most nearly means:
Show the answer
C. bene- means well, dict means say, and -ion makes a noun: the act of saying good words. A curse is the opposite, a malediction. A good deed stops at bene- and forgets dict, and a dictionary uses only dict. Benediction most nearly means a blessing.
Incredulous most nearly means:
Show the answer
B. in- means not and cred means believe, so the person does not believe. The suffix matters: -ible means can be, so incredible describes a thing that can hardly be believed; -ous (here -ulous) means full of, so incredulous describes a person full of disbelief. That is why amazing is a trap. Trusting drops the in-, and unknown is a guess. Incredulous most nearly means disbelieving.
Antipathy most nearly means:
Show the answer
A. anti- means against and path means feeling: a feeling against someone. Deep sympathy uses sym-, together, and lack of feeling is apathy, with a- meaning without. A walking path reads path as an English word, not the Greek root. Antipathy most nearly means strong dislike.
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