Word Roots and Prefixes
This list contains some of the common roots and prefixes that make up the
building blocks of numerous English words. Following the table of general roots
and prefixes is a table of number prefixes. How Words Work
Many words are made up of a root (or base word) and a
prefix. Some words also have a suffix. For example, the root word port
means to carry or to bear. Attach the prefix ex, meaning out
or out of, and you have the word export, to carry out. Attach the
prefix im, meaning in or into and you have import, to
carry in. Attach the prefix trans, meaning across, and you
have transport, meaning to carry across. Now let's attach the
suffix able, meaning able to be, and you have importable,
exportable, and transportable.
The very words prefix and suffix are good examples, too. Pre
means before and fix means to fasten or attach, so quite
literally, a prefix is something attached to the beginning of something else. Suf
is a variant of sub, below or under, so a suffix is something fastened
underneath something else (in this case, behind the root). 
By
learning the common roots and prefixes (and a few suffixes) you will be able to
discern the meaning of many new words almost immediately. (But do look them up
for confirmation.) Take the word abject, for example. If you know that ab
means away or down and ject means to throw, you can easily
figure out that abject doesn't mean something happy. Rather abject's
root meaning of thrown down is quite close to the dictionary
defintion of cast down in spirit or sunk into depression.Now that you have learned that ject means to throw, think how many words you can define almost immediately: reject, project, inject, subject, eject, and so on. Roots are a real key to understanding the meaning of new words you come across in your reading.
Note that some modern words are formed by using abbreviated forms of other words. Thus, we see the use of the letter i for Internet in iPhone, iPod, and iTunes, indicating that these items or services work with the Internet. Similarly, the use of e for electronic appears in words such as elearning (and various forms: eLearning, E-Learning, and so on), e-commerce, and e-business. The "e-terms" seem to have been coined before the "i-terms" became popular. And note that most of the "i-terms" are trademarks, while the others are general descriptors: "I'm going to download some iTunes from Apple's e-commerce site because I love e-music." At any rate, these abbreviated forms are not traditional prefixes, but because they are indeed attached to the front of what amounts to root words, they could be considered functional prefixes.
General Roots and Prefixes
|
Root or Prefix
|
Meaning
|
Examples
|
|
a, an
|
not, without
|
atheist, anarchy, anonymous apathy, aphasia, anemia, atypical,
anesthesia
|
|
ab
|
away, down, from, off
|
absent, abduction, aberrant, abstemious, abnormal,
abstract, absorb
|
|
acro
|
high, tip, top
|
acrobat, acrophobia, acronym, acromegaly, acropolis
|
|
act
|
do, move
|
action, react, transaction, proactive, activity,
activation, deactivate
|
|
ad
|
to, toward
|
admit, addition, advertisement, adherent, admonish,
address, adhesive, adept, adjust
|
|
alt
|
high
|
altitude, altimeter, alto, contralto, altocumulus, exalt
|
|
ambul
|
to walk
|
ambulatory, amble, ambulance, somnambulist, perambulate,
preamble
|
|
anima
|
soul, life
|
animation, inanimate, animal, anime, equanimity, animism,
animus
|
|
ante
|
before
|
anteroom, antebellum, antedate antecedent, antediluvian
|
|
anti, ant
|
against, opposite
|
antisocial, antiseptic, antithesis, antibody, antichrist,
antinomies, antifreeze, antipathy, antigen, antibiotic, antidote, antifungal,
antidepressant
|
|
arm
|
weapon
|
army, armament, disarm, rearm, armistice, armor, armory,
arms
|
|
audi
|
to hear
|
audience, auditory, audible, auditorium, audiovisual, audition,
audiobook
|
|
auto
|
self
|
automobile, automatic, autograph, autonomous, autoimmune,
autopilot, autobiography
|
|
be
|
thoroughly
|
bedecked, besmirch, besprinkled, begrudge, begrime, belie,
bemoan
|
|
bell
|
war
|
belligerent, antebellum, bellicose, rebel
|
|
bene
|
good, well
|
benefactor, beneficial, benevolent, benediction,
beneficiary, benefit
|
|
bi
|
two
|
bicycle, bifocals, biceps, billion, binary, bivalve,
bimonthly, bigamy, bimetal, biathlete, bicarbonate
|
|
bio
|
life, living
|
biology, biography, biodiversity, bioavailability,
bioflavonoid, biofuel, biohazard, biomass, biorhythm
|
|
cede, ceed, cess
|
to go, to yield
|
succeed, proceed, precede, recede, secession, exceed, succession,
excess
|
|
chron
|
time
|
chronology, chronic, chronicle, chronometer, anachronism
|
|
cide, cis
|
to kill, to cut
|
fratricide, suicide, incision, excision, circumcision,
precise, concise, precision, homicide, genocide, regicide
|
|
circum
|
around
|
circumnavigate, circumflex, circumstance, circumcision, circumference,
circumorbital, circumlocution, circumvent, circumscribe, circulatory
|
|
clud, clus claus
|
to close
|
include, exclude, clause, claustrophobia, enclose,
exclusive, reclusive, conclude, preclude
|
|
con, com
|
with, together
|
convene, compress, contemporary, converge, compact, confluence,
concatenate, conjoin, combine, convert, compatible, consequence, contract
|
|
contra, counter
|
against, opposite
|
contradict, counteract, contravene, contrary, counterspy,
contrapuntal, contraband, contraception, contrast, controversy, counterfeit,
counterclaim, counterargument, counterclaim, counterpoint, counterrevolution
|
|
cred
|
to believe
|
credo, credible, credence, credit, credential, credulity,
incredulous, creed, incredible
|
|
commun
|
to share
|
commune, community, communism, communicable, communication,
commonality, incommunicado
|
|
cycl
|
circle, wheel
|
bicycle, cyclical, cycle, encliclical, motorcycle,
tricycle, cyclone
|
General Roots and Prefixes (continued)
|
Root or Prefix
|
Meaning
|
Examples
|
|
de
|
from, down, away
|
detach, deploy, derange, deodorize, devoid, deflate, degenerate,
deice, descend, derail, depress, depart, decompose, destruction
|
|
dei, div
|
God, god
|
divinity, divine, deity, divination, deify, deism
|
|
demo
|
people
|
democracy, demagogue, epidemic, demographic, endemic
|
|
dia
|
through, across, between
|
diameter, diagonal, dialogue, dialect, dialectic,
diagnosis, diachronic, diagram, diaphragm, dialysis, diarrhea
|
|
dict
|
speak
|
predict, verdict, malediction, dictionary, dictate,
dictum, diction, indict, contradict
|
|
dis, dys, dif
|
away, not, negative
|
dismiss, differ, disallow, disperse, dissuade, disconnect,
dysfunction, disproportion, disrespect, distemper, distaste, disarray,
dyslexia
|
|
duc, duct
|
to lead, pull
|
produce, abduct, product, transducer, viaduct, aqueduct, induct,
deduct, reduce, induce
|
|
dyn, dyna
|
power
|
dynamic, dynamometer, heterodyne, dynamite, dynamo, dynasty
|
|
ecto
|
outside, external
|
ectomorph, ectoderm, ectoplasm, ectopic, ectothermal
|
|
endo
|
inside, within
|
endotoxin, endoscope, endogenous
|
|
equi
|
equal
|
equidistant, equilateral, equilibrium, equinox, equitable,
equation, equator
|
|
e, ex
|
out, away, from
|
emit, expulsion, exhale, exit, express, exclusive,
enervate, exceed, explosion, eject, exude
|
|
eu
|
good, pleasant
|
euphoria, euphemism, eustress, euphonic, eukaryote
|
|
exter, extra
|
outside of
|
external, extrinsic, exterior, extraordinary,
extrabiblical, extracurricular, extrapolate, extraneous, exterminator, extract,
extradite, extraterrestrial, extrasensory, extravagant, extreme
|
|
flu, flux
|
flow
|
effluence, influence, effluvium, fluctuate, confluence,
reflux, influx
|
|
flect, flex
|
to bend
|
flexible, reflection, deflect, circumflex, inflection,
reflex
|
|
graph, gram
|
to write
|
polygraph, grammar, biography, graphite, telegram, autograph,
lithograph, historiography, graphic, electrocardiogram, monogram
|
|
hetero
|
other
|
heterodox, heterogeneous, heterosexual, heterodyne
|
|
homo
|
same
|
homogenized, homosexual, homonym, homophone
|
|
hyper
|
over, above
|
hyperactive, hypertensive, hyperbolic, hypersensitive,
hyperventilate, hyperkinetic, hyperlink, hypertext, hypersonic, hypertrophy
|
|
hypo
|
below, less than
|
hypotension, hypodermic, hypoglycemia, hypoallergenic, hypothermia,
hypothesis
|
General Roots and Prefixes (continued)
|
in, im
|
not
|
inviolate, innocuous, intractable, innocent, impregnable,
impossible, incapable, incoherent, impassible, impotent
|
|
infra
|
beneath
|
infrared, infrastructure, infrasonic
|
|
inter, intro
|
between
|
international, intercept, intermission, interoffice,
internal, intermittent, introvert, introduce
|
|
intra
|
within, into
|
intranet, intracranial, intravenous, intramural,
intramuscular, intraocular
|
|
jac, ject
|
to throw
|
reject, eject, project, trajectory, interject, dejected,
inject, ejaculate
|
|
log, logo, loc, loq
|
word, speech, speak
|
monologue, dialogue, locution, colloquial, elocution,
soliloquy, ventriloquist, apology, doxology, epilogue, logic, eulogy,
loquacious
|
|
mal
|
bad, badly
|
malformation, maladjusted, dismal, malady, malcontent, malfeasance,
maleficent, malevolent, malice, malaria, malfunction, malignant
|
|
mega
|
great, million
|
megaphone, megalomaniac, megabyte, megalopolis, acromegaly
|
|
meso
|
middle
|
mesomorph, mesoamerica, mesosphere
|
|
meta
|
beyond, change
|
metaphor, metamorphosis, metabolism, metahistorical, metainformation,
metacognitive, metaphysics
|
|
meter
|
measure
|
perimeter, micrometer, ammeter, multimeter, altimeter,
geometry, kilometer
|
|
micro
|
small
|
microscope, microprocessor, microfiche, micrometer, micrograph
|
|
mis
|
bad, badly
|
misinform, misinterpret, mispronounce, misnomer, mistake,
misogynist, mistrial, misadventure, misanthrope, misread
|
|
mit, miss
|
to send
|
transmit, permit, missile, missionary, remit, admit,
missive, mission
|
|
morph
|
shape
|
polymorphic, morpheme, amorphous, metamorphosis, morphology,
morphing
|
|
multi
|
many
|
multitude, multipartite, multiply, multipurpose,
multicolored, multimedia, multinational
|
|
neo
|
new
|
neologism, neonate, neoclassic, neophyte
|
|
non
|
not
|
nonferrous, nonabrasive, nondescript, nonfat, nonfiction,
nonprofit, nonsense, nonentity
|
|
omni
|
all
|
omnipotent, omnivorous, omniscient, omnibus, omnirange,
omnipresent
|
|
pan
|
all, whole, general, completely
|
pantheism, pandemic, panacea, panoply, pan-American, panchromatic,
pandemonium, panorama
|
|
para
|
beside
|
paraprofessional, paramedic, paraphrase, parachute, paralegal,
parallel, comparison
|
|
per
|
through, intensive
|
permit, perspire, perforate, persuade, perceive, perfect,
permit, perform, pervasive
|
|
peri
|
around
|
periscope, perimeter, perigee, periodontal, pericope
|
|
phon
|
sound
|
telephone, phonics, phonograph, phonetic, homophone, microphone
|
|
phot
|
light
|
photograph, photosynthesis, photon
|
|
poly
|
many
|
polytheist, polygon, polygamy, polymorphous
|
|
port
|
to carry
|
porter, portable, report, transportation, deport, import,
export
|
General Roots and Prefixes
|
Root or Prefix
|
Meaning
|
Examples
|
|
re
|
back, again
|
report, realign, retract, revise, regain, reflect, rename,
restate, recombine, recalculate, redo
|
|
retro
|
backwards
|
retrorocket, retrospect, retrogression, retroactive
|
|
sanct
|
holy
|
sanctify, sanctuary, sanction, sanctimonious, sacrosanct
|
|
scrib, script
|
to write
|
inscription, prescribe, proscribe, manuscript, conscript,
scribble, scribe, postscript, transcript
|
|
sect, sec
|
cut
|
intersect, transect, dissect, secant, section
|
|
semi
|
half
|
semifinal, semiconscious, semiannual, semimonthly, semicircle
|
|
spect
|
to look
|
inspect, spectator, circumspect, retrospect, prospect, spectacle
|
|
sub
|
under, below
|
submerge, submarine, substandard, subnormal, subvert, subdivision,
submersible, submit
|
|
super, supra
|
above
|
superior, suprarenal, superscript, supernatural,
supercede, superficial, superhero, superimpose
|
|
syn
|
together
|
synthesis, synchronous, syndicate, synergy, snyopsis,
syncretism
|
|
tele
|
distance, from afar
|
television, telephone, telegraph, telemetry, telepathy,
teleconference
|
|
theo, the
|
God
|
theology, theist, polytheist, pantheism, atheist,
monotheist, theophany
|
|
therm, thermo
|
heat
|
thermal, thermometer, thermocouple, thermodynamic,
thermoelectric
|
|
tract
|
to drag, draw
|
attract, tractor, traction, extract, retract, protract,
detract, subtract, contract, intractable
|
|
trans
|
across
|
transoceanic, transmit, transport, transducer, transit,
intransitive
|
|
un
|
not
|
uncooked, unharmed, unintended, unhappy, unenlightened,
unremarkable
|
|
veh, vect, vey
|
to carry
|
vector, vehicle, convection, vehement, convey, conveyance,
conveyor
|
|
vert, vers
|
to turn
|
convert, revert, advertise, versatile, vertigo, invert,
reversion, extravert, introvert
|
|
ven, vent
|
to come
|
convention, prevent, intervention, convent, Advent,
invent, inventory
|
|
verm
|
worm
|
vermin, vermicelli, vermiculite, vermicide, vermiform,
vermilion
|
|
vita
|
life
|
vital, vitality, vitamins, revitalize
|
|
vol
|
to will
|
benevolent, volition, voluntary, malevolent
|
Number Prefixes
|
Prefix
|
Meaning
|
Examples
|
|
mono, uni
|
one
|
monopoly, monotype, monologue, mononucleosis, monorail,
monotheist, unilateral, universal, unity, unanimous, uniform
|
|
bi, di
|
two
|
divide, diverge, diglycerides, bifurcate, biweekly,
bivalve, biannual, billion
|
|
tri
|
three
|
triangle, trinity, trilateral, triumvirate, tribune,
trilogy, tricycle, trillion
|
|
quat, quad
|
four
|
quadrangle, quadruplets, quaternary, quarter, quadrillion
|
|
quint, penta
|
five
|
quintet, quintuplets, pentagon, pentane, pentameter,
quintillion
|
|
hex, ses, sex
|
six
|
hexagon, hexameter, sestet, sextuplets, sextillion
|
|
sept
|
seven
|
septet, septennial, septillion, September
|
|
oct
|
eight
|
octopus, octagon, octogenarian, octave, octillion, October
|
|
non
|
nine
|
nonagon, nonagenarian, nonillion
|
|
dec
|
ten
|
decimal, decade, decalogue, decimate, decillion, December
|
|
cent
|
hundred
|
centennial, century, centipede, centillion
|
|
mill, kilo
|
thousand (10^3)
|
millennium, kilobyte, kiloton
|
|
mega
|
million (10^6)
|
megabyte, megaton, megaflop, megawatt
|
|
giga
|
billion (10^9)
|
gigabyte, gigaflop, gigahertz, gigawatt
|
|
tera
|
trillion (10^12)
|
terabyte, teraflop, terawatt
|
|
peta
|
quadrillion (10^15)
|
petabyte
|
|
exa
|
quintillion (10^18)
|
exabyte
|
|
zetta
|
sextillion (10^21)
|
zettabyte
|
|
yotta
|
septilion (10^24)
|
yottabyte
|
|
milli
|
thousandth (10^-3)
|
millisecond, milligram, millivolt, milliwatt, millimeter,
millipede
|
|
micro
|
millionth (10^-6)
|
microgram, microvolt, microwave, microsecond
|
|
nano
|
billionth (10^-9)
|
nanosecond, nanobucks, nanofarad, nanometer, nanomachine,
nanotube, nanotechnology, nanogram, nanoscale
|
|
pico
|
trillionth (10^-12)
|
picofarad, picocurie, picogram, picomole, picosecond
|
|
femto
|
quadrillionth (10^-15)
|
femtosecond
|
|
atto
|
quintillionth (10^-18)
|
attosecond, attometer
|
|
zepto
|
sextillionth (10^-21)
|
zeptosecond
|
|
yocto
|
septillionth (10^-24)
|
yoctosecond
|
