When you type a partial word into Google,  search results often are returned with completed words. Try a search for “partici poin” without the quotation marks. Notice that Google decides that you meant “participation points” by the looks of the results. How is this?

Theory: Google might first notice the fact that your search is for strings or text that seem to be far removed from the common lexicon (Google’s dictionary of common search terms or search strings). Google may further notice that you have queried for a “phrase” or set of strings that have never been searched for. At this point Google sees that your strings can be stripped back to known roots. In this case “par” and “po”.

Google then looks at the possible strings for each root in combination to find a commonly used phrase “participation points”. There is also the possibility that Google simply scans for words or other strings that contain your incomplete strings (substrings), then looks for commonly used phrases in the order you’ve entered your strings. Just how Google does any of this is known.

If you search for “par po” Google makes a completely different set of associations, such as the acronym PO for Post Office and the town of Par. In this case, Google may see the string as being complete, as it certainly does qualify for that treatment, having strings that can be matched to strings in the common lexicon and as such are considered to be full units of meaning.

Searching for “parti po,” yields an associaed French word and an acronym POI.

“partic poin” has a strong association with “Patrick’s Point” a park in California. It is only with the extra “i” attached to “partic” for “partici” that Google makes the strong association with “participation points”.

One must wonder why this is.

Below are some of the common roots, suffixes and prefixes in English. This may help you decipher what exactly Google does with our partial search strings for those of us who dabble in such.

alterotheralternate, alter ego
ami, amic-loveamiable, amicable
amphiboth ends or all sidesamphibian
ann, enniyearanniversary, annual, biennial, perennial
anthrophuman, mananthropology, anthropomorphic, misanthrope
aqua, aquewateraquatic, aquarium, aqueduct
archchief, leader, rulerarchangel, monarch, archaic, archenemy
audsoundauditorium, audible, audiologist, audiotape
bellwarbelligerent, bellicose
bibliobookbibliography, bibliophile
bio-lifebiography, autobiography, biology, antibiotic
brevshortbrief, abbreviate
captake, seizecapture, captivate, capacity
carnmeatcarnivorous, chili con carne
cedyield, gorecede, secede, proceed, intercede, concession
chrom-colorchromatic, monochrome, polychrome
chron-timechronicle, chronology, chronometer, synchronize
cognknowrecognize, cognitive, incognito
corpbodycorpus, corpse, corporal
crac, cratrule, rulerautocrat, democracy, bureaucrat, democracy
credbelievecredible, credulous, credibility, credit, credo
cruccrosscrucifix, crucial
crypthiddencryptogram, cryptology, cryptic
culpguiltculpable, culprit
deigoddeity, deify
demo-peopledemography, democracy, epidemic
denttoothdentist, dentifrice, dentin
derm-skindermatology, epidermis, hypodermic
dicspeak, saydictate, predict, diction, indict
doxbelief, opinionorthodoxy, paradox, heterodoxy
duc, ductleadinduce, deduce, seduction, conduct, abduct
dynam-powerdynamo, hydrodynamics
egoselfegotist, egomania
equequalequal, equity, equanimity, equate, equidistant
facmake, domanufacture, factory, benefactor
fraterbrotherfraternal, fraternize
gam-marriagemonogamy, polygamy, bigamy
geo-earthgeopolitical, geology, geography, geothermal
glyphvertical grooveHieroglyphics—Egyptian “sky writing”
grad, gressstepgradual, progression, transgression
graph-writing, printinggraphology, biography, telegraph, geography
gyn-womangynecologist, androgynous
hemo, hema, hembloodhemophilia, hematology, hemoglobin
holowhole, entireholograph
hydro, hydrwaterdehydrate, hydraulics, hydroelectric, hydroplane
isoequal, identicalisolate
jectthrowinject, reject, subject, projection
judjudgejudicial, judge, adjudicate
leg, lectread, chooselegible, lectern, lecturer, election
literletterliterature, illiterate, literal
locplacelocal, location
logwordmonologue, epilogue
luclightlucid, elucidate
magnlargemagnify, magnate, magnificent
manhandmanufacture, manual, manuscript
marseamarine, mariner
matermothermaternal, maternity, matriarchy, matricide
merepart, segmentmere
meta, metbehind, betweenmetacognition—behind the thinking
metri, meter-measuregeometric, thermometer, odometer
minsmallminority, minuscule, minute
mit, misssendpermit, submission, mission, emit,
mob, mot, movmovemobile, automobile, motion, promote, movie
monwarnpremonition, admonition
mor, mortdeathmortal, mortician, immortality
morphform, structuremetamorphosis, amorphous, morphology
mutchangemutant, mutability, mutate
neuronerveneurology, neurosis, neurobiology
nomen /nominnamenominal, nominate, nomenclature
novnewnovel, renovate, innovation, novella
nym, onymword, namesynonym, acronym, anonymous, pseudonym
odontotoothorthodontist—one who straightens teeth
ortho-straight, correctorthodox, orthodontist, orthopedic
pacpeacepacify, Pacific Ocean, pacifist
paraequal, throughpar, participant, parallel, comparable
paterfatherpaternal, paternity, patricide, patrilineal, patriotic
pathfeeling, sufferingsympathy, apathy, empathy, telepathy, pathology
ped, podfootpedal, pedometer, centipede, gastropod
pel, pulspushpulsate, repulsive, impulse, compel, propel
pendhang, weighpendulum, pendant, suspend, pending
phon-, phono-sound, voicetelephone, euphony, cacophony, phonograph
planflatplanar, plantation, plane
popoint, place, unit, people, energypoint, population, potential, position
portcarryportable, transport, portage, report,
potpowerpotent, omnipotent, potentate
psych-soul, spirit, mindpsychology, psychic, psychobiography
pugnafightpugnacious, pugilist
quer, quisaskquery, inquisition,
scent, scendclimbascend, ascent
schizo, schizdivision, splitschizophrenic
scrib, scriptwritemanuscript, scribe, proscribe, scripture
sec, sectcutdissect, section
sed, sesssitsedentary, session
sens, sentfeel, be awaresensible, sentient
sequ, secufollowsequence, sequel, consecutive
servserve, protectservice
similsamesimilar, assimilate, simile, facsimile (fax)
sonsoundsonar, resonate, unison
sophwisdom, knowledgephilosophy, sophisticated, sophomore (wise fool)
spec, spiclook, seespectacles, spectator, inauspicious, prospect
spirbreatheinspire, respiration, conspire, perspiration
spond, sponspromise, answer forrespond, responsible
spontby one’s own forcespontaneous
statstay, positionstation
tang, tacttouchtactile, tangible
temptimetemporary, temporize
ten, tentholdtentative, tenable, tenuous
terrearthsubterranean, terrain, terrestrial, disinter
theogod, deitytheology, polytheism, atheist, monotheism
therm-heatthermal, thermos, thermometer
trophynutrition, foodatrophy—without nutrition
vacemptyvacation, vacuum, vacuous, vacant
ven, ventcome, gointervene, convene, contravene
vertruthveracity, verify, verity
vertturnintrovert, irreversible, vertigo
vitlifevital, revitalize, vitamin
voccallrevoke, invocation, vocal, evocative, convocation
zooanimalzoo, zoology, zoolatry

a-, an-not, withoutamoral, anesthetic, apolitical,asocial
ab-away fromabduction, abstain, abnormal
ad-to, towardadjoin, adjacent (lying near to)
ambi-bothambidextrous, ambivalent
ana-up, back, againanalogy, anatomy, anagram
anti-againstantipathy, antiwar, antisocial
apo-from, away fromapology, apologize
auto-selfautobiography, automobile,autocracy, automaton
bene-goodbenediction benevolent benefactor
cata-, cat-down, againstcatastrophe–a turning down
centro, centri-around, centerconcentric, centrifugal
circum-aroundcircumlocution circumference,circumvent
com-with, togethercommunal, community
con-with, togetherconnect, confide conspire
contra-againstcontradict, contravene
de-down, awaydescend, deject (cast down)
dia-, di-through, acrossdiameter, division
dis-apart, notdisengage, discord, discomfort
dys-ill, difficult, baddysfunctional, dysentery
e-out of, fromelect (choose out of), eject (throwout)
ecto-on the outsideectoderm–outer skin
en-, em-inempathy–feeling in
endo-within, insideendoscope–instrument for observinginside
epi-uponepitaph epidermis, epicenter
eso-inward, withinesoteric–more inward, esophagus
eu-well, goodeuthanasia–good death
ex-out of, fromexhume, exhale, exodus
hetero-other, differentheterosexual, heterodoxy, heterodoxheterogeneous
homo-samehomosexual, homogeneous, homogenized
hyper-overhypertension, hypersensitive,hyperactivity
hypo-underhypotension, hypodermic
il-notillegitimate, illicit, illegal,illegible
im-notimperfect, impolite, impossible
im-intoimbibe (drink in, take in)
in-notindiscreet, invisible
in-intoincorporate (take into the body)
inter-betweenintervene (come between), interstate
intra-withinintrastate, intramural
ir-notirregular, irrational, irredeemable
macro-largemacrocosm, macroeconomics
mal, male-bad, evilmalediction malevolent, malnutrition
micro-smallmicroscope, microcosm,microeconomics
mono-one, singlemonologue, monotheism, monarchy,monogamy
neo-new, recentneologism, neo-liberal, neonatology.neolithic
ob-againstobject, obstruct (build against)
palin-, pali-back, againpalindrome
pan-all, everypantheism, Pan-Hellenic, panorama,pandemic
para-falseparamilitary, paralegal, parachute
per-throughpercolate (flow through) perforate(punch through)
peri-aroundperimeter, periscope
phil-, philo-like, lover ofphilosophy, Francophile,bibliophile, philanthropy
poly-many, severalpolygon, polygamy, polytechnic,polytheism
post-afterpostgraduate, posthumous postpone
pre-beforeprecede, predict (tell before)
pro-for, forwardpromote, project
pros-toward, in frontprospect—view in front, somethingcoming up
proto-firstprototype, protoplasm, protobiology
pseudofalsepseudonym, pseudoscience
re-again, backrepeat, recede, regress (step back)
retro-backretrogression, retroactive
se-away fromseduce (lead away), secede
sub-undersubmarine, subject, subhumansubterranean
sur-, super-over, abovesuperhuman, superego, superintend,surpass
syn-, sym-, syl-, sys-with, togethersymphony, synonym, system, syllable
tele-distant, far offtelephone, telepathy, television,telegram
trans-acrosstransient, Transatlantic, transport(carry across)

-agog, -agogueleaderdemagogue, pedagogue
-cidekill(ing)patricide, infanticide, herbicide.suicide
-ectomycuttingappendectomy, splenectomy
-ia, -yact, stateamnesia, mania, democracy, anarchy
-ic, -tic, -ical, -achaving to do withanthropomorphic, dramatic, biblical,cardiac
-icsthings having to do withoptics, physics
-isk, -iscussmallasterisk–a little star
-ismthe belief inpacifism, terrorism, socialism,communism
-istone who believes inpacifist, terrorist, socialist,communist
-iteone connected withmeteorite, polite, cosmopolite
-logystudy field ofbiology, geology, etymology,cardiology
-oidresembling, like-shapedasteroid, spheroid
-or, -erone who takes part indoctor, actor, teacher, driver
-phobiaexaggerated fearphotophobia, claustrophobia,agoraphobia
-sisact, state, condition ofanalysis