by Susan Thorpe
Word Ways, August 1999


My FAVOURITE words are those in which the five vowels A, E, I, O and U each occur just once. They are referred to as AEIOU words. Over the last 30 years, Word Ways contributors have tried to find examples of these words to satisfy all 120 permutations of the five vowels. Whilst it is relatively easy to find several examples for many of the permutations, for others it is a struggle to find even one. Here, to begin with, is the story of the AEIOU quest.


It all started back in the November 1969 issue of Word Ways with Ross Eckler's article Unsociable Housemaid Discourages Facetious Behaviour. Ross was seeking at least one uncapitalised English word to satisfy each of the 120 AEIOU permutations. Initially, with the help of Dmitri Borgmann and Darryl Francis, he found one or more words for 104 of the 120 permutations. In the February 1970 issue he added LARYNGOFISSURE (AOIUE), FIEULAMORT (IEUAO) - with Darryl Francis, PYROCATECHUIC (OAEUI), UNPRAISEWORTHY (UAIEO) and PULVERIZATOR (UEIAO), all from Webster's Second Edition. [It is also worth noting that, in February 1970, VIOLATURE (IOAUE) and MULTIRAMOSE (UIAOE), both in Webster's Second, were offered as replacements for non-Websterian examples.] Thus, by 1970, a total of 109 of the permutations had been catered for, leaving 11 gaps: AEIUO, AUIEO, EAIUO, IAEUO, IAUEO, IEAUO, IUEOA, OAIEU, OAUEI, OEIAU and UIAEO. Since that time, examples have been found to fill these gaps (below) but only some of them adhere to the 'uncapitalised English words' constraint. Here is a timetable of events:

Feb 1970
Feb 1975
Feb 1975
May 1977
May 1979
May 1979
Aug 1985
Nov 1993
Feb 1994
Feb 1994
Feb 1994
Feb 1994
Feb 1994
Andrew Griscom
Darryl Francis
Darryl Francis
Philip Cohen
Sir Jeremy Morse
Sir Jeremy Morse
Murray Geller
Susan Thorpe
Susan Thorpe
Chris Long
Chris Long
Chris Long
Chris Long
UIAEO Cuitlateco (Web2)
OAUEI opaqueing (OED1 cit)
EAIUO sea-liquor (CD)
OAIEU Ornacieux (OSN France)
IUEOA picture-board (OED)
IAEUO village burrow (OED)
OEIAU Oeciacus (Web3)
AEIUO Laeviturbo (NZ)
IUEOA milquetoast (Web3)
AUIEO cauilero (OED)
AUIEO Marquisedom (OED)
IAUEO lillabullero (OED cit)
IEAUO Ierfaulcon (OED cit)
2-word phrase

So, by February 1994, all 11 gaps had been filled. Incredibly, it had taken nearly 25 years to find at least one example to represent each of the 120 AEIOU permutations!


Five more years have now elapsed and 1999 marks the 30th anniversary of the inception of the AEIOU quest. Those less than perfect examples still reside in our list. Can we get rid of any of them? I decided it was time to search for improvements. As a result, I can now offer the following alternatives:

Aug 1999
Aug 1999
Aug 1999
Aug 1999
Aug 1999
Aug 1999
Susan Thorpe
Susan Thorpe
Susan Thorpe
Susan Thorpe
Susan Thorpe
Susan Thorpe
AEIUO cane-liquor (Web2)
EAIUO recapitulor (OED cit)
IAEUO inaequo (CLD)
OAIEU containerful (BT)
OEIAU coeliacus (Web3)
UIAEO quinaseptol (CDS)

Readers will have to decide for themselves whether or not hyphenated words are preferable to capitalised words; and whether they prefer single, unhyphenated Latin words to the examples previously found.

In List A below, the 109 non-italicised words are Ross Eckler's 1969 and 1970 contributions. The italicised words are subsequent additions.


In the May 1979 Word Ways, David Shulman presented An AEIOU Examination. This was an exercise to find words for as many of the 120 AEIOU permutations as possible from a single source - Funk and Wagnall's Standard College Dictionary. He found 283 words, to which Ross Eckler added another 80. These 363 words represented 68 of the 120 permutations but, unfortunately, none filled any of the gaps pertaining at the time. Shulman's particular approach to the AEIOU hunt started me thinking... would it be possible to satisfy all 120 permutations with words taken from any single dictionary? Admittedly this sounds rather ambitious. Being patriotic, I decided to try the single dictionary exercise with that British bible, the Oxford English Dictionary Second Edition. I imposed only two constraints, being very aware of how restrictive those two words 'uncapitalised' and 'English' had proved to be. Firstly, the words must appear somewhere in the OED, be it as head words, variant forms, or words in the text including citations. When provided with a choice, I gave preference to head words. The second constraint was not to repeat any of the words which appeared in List A. The results of my OED searches are given in List B below. I was successful in finding at least one OED word (in some cases only one word) for each of the 120 permutations. Initially I didn't quite meet my second target, four words appearing in both List A and List B. However, I managed to release these words for exclusive use in List B by finding List A replacements, the permutations concerned being AIEUO, IAUEO, IEAUO and IUEOA. Thus my second goal had also been achieved, all 120 OED words in List B being different from the words in List A. Implicitly this means that, overall, at least two words of some description have now been found to represent each of the 120 AEIOU permutations. The fact that none of the words in List B is hyphenated and only one, Ierfaulcon (IEAUO), capitalised is a bonus.

In these lists, a word shown in brackets is the head word under which the listed word can be found. Where relevant, it is followed by a citation date. A variant form is shown by vf.


BT= Bloomsbury Thesaurus 1993
CLD = Cassell's Latin Dictionary 1948
CD(S) = Century Dictionary 1889-91 (Supplement 1909)
Dor = Dorland's Medical Dictionary
NZ = Nomenclator Zoologicus
OED1 = Oxford English Dictionary 1st edition
OED = Oxford English Dictionary 2nd edition
OSN = Official Standard Names Gazetteer
Sted = Stedman's Medical Dictionary
TIG = Times Index Gazetteer of the World
WebC5 = Webster's Collegiate Dictionary 5th edition
WebC7 = Webster's Collegiate Dictionary 7th edition
Web2 = Webster's New International Unabridged Dictionary 2nd edition
Web3 = Webster's New International Unabridged Dictionary 3rd edition


        LIST A                                        LIST B
AEIOU   facetious (WebC7)                             caesious                         
AEIUO   Laeviturbo (NZ), cane-liquor (Web2)           aegritudo (aegritude)            
AEOIU   pandemonium (WebC7)                           archesporium (archespore)        
AEOUI   haemofuscin (Web2)                            warehousing                      
AEUIO   maleruption (Web2)                            flabergudgion                    
AEUOI   aneuploid (Web3)                              aequorin                         
AIEOU   ambidextrous (WebC7)                          aireous                          
AIEUO   archineuron (Web2)                            antineutrons (anti- 1942)        
AIOEU   carillonneur (WebC7)                          raisonneur                       
AIOUE   grandiloquent (WebC7)                         graciousness                     
AIUEO   antinucleon (Web3)                            adinuencyons (adinvention 1413)  
AIUOE   radiculose (Web3)                             ramiculose                       
AOEIU   apothecium (WebC7)                            macrotherium (macrothere)        
AOEUI   allotelluric (Web2)                           manoeuvring                      
AOIEU   amortisseur (Web3)                            agonieux (agony)                 
AOIUE   laryngofissure (Web2)                         acrostique (vf acrostic)         
AOUEI   accoutering (WebC7)                           assouerit                        
AOUIE   tambourine (WebC7)                            savouriness                      
AUEIO   aculeiform (Web3)                             haugersion                       
AUEOI   aureomycin (Web3)                             aureolin                         
AUIEO   cauilero (OED)                                alumineor (alluminor)            
AUIOE   cauliflower (WebC7)                           cautioned                        
AUOEI   autosexing (WebC7)                            tautomerism                      
AUOIE   authorize (WebC7)                             vacuolized                       
EAIOU   behaviour (WebC7)                             mendacious                       
EAIUO   sea-liquor (CD), recapitulor(OED -head 1678)  beatitudo (beatitude)            
EAOIU   crematorium (WebC7)                           metapodium                       
EAOUI   reavouching (Web2)                            enamouring                       
EAUIO   exhaustion (WebC7)                            reassumption                     
EAUOI   tentaculoid (Web3)                            pennatuloid                      
EIAOU   pedimanous (Web3)                             epiphanous                       
EIAUO   semiauto (Web3)                               peliagudo (sharp 1755)           
EIOAU   plesiosaur (WebC7)                            periostracum                     
EIOUA   ventriloqual (WebC5)                          heliofugal                       
EIUAO   gesticulatory (WebC7)                         recirculatory                    
EIUOA   semicupola (Web2)                             ventriculography                 
EOAIU   endocardium (WebC7)                           neopallium                       
EOAUI   seroalbumin (Web2)                            menopausic                       
EOIAU   neostriatum (Web3)                            excoriatus (flay c1440)          
EOIUA   dentolingual (WebC5)                          precommisural                    
EOUAI   encouraging (WebC7)                           depopulating                     
EOUIA   dentosurgical (WebC5)                         precommunicant                   
EUAIO   education (WebC7)                             equation                         
EUAOI   euharmonic (Web3)                             eukaryotic                       
EUIAO   repudiator (WebC7)                            elucidator                       
EUIOA   equivocal (WebC7)                             equimolar                        
EUOAI   neuropathic (WebC7)                           eustomachic                      
EUOIA   sequoia (WebC7)                               neurotically                     
IAEOU   intravenous (WebC7)                           filamentous                      
IAEUO   village burrow (OED), inaequo (CLD)           invaletudo (invaletude)          
IAOEU   citharoedus (Web2)                            cinnamomeus (flat 1859)          
IAOUE   miaoued (WebC5)                               dialogue                         
IAUEO   diauchenos(Dor)                               lillabullero (Lillibullero 1782) 
IAUOE   disaccustomed (WebC7)                         triantulope (vf triantelope)     
IEAOU   tricephalous (Web3)                           dipetalous                       
IEAUO   printer-author (OED - printer)                Ierfaulcon (gyrfalcon 1580)      
IEOAU   diesophagus (?) - is in Dor                   interrogatus (Hanse 1279)        
IEOUA   intercolumnar (Web3)                          intercommunal                    
IEUAO   fieulamort (Web3)                             dimensurator                     
IEUOA   interpulmonary (Web3)                         irreuocably (consistory 1502)    
IOAEU   lithofracteur (Web2)                          icosaedrum (vf icosahedron)      
IOAUE   isopaque (?), violature (Web2)                microcapsule                     
IOEAU   hippocentaur (Web3)                           microcephalous                   
IOEUA   incommensurably (WebC7)                       inopercular                      
IOUAE   discourage (WebC7)                            incomputable                     
IOUEA   isonuclear (Web3)                             micronuclear                     
IUAEO   linguaeform (Web3)                            stipulaeform                     
IUAOE   fistulatome (Web2)                            linguaphone                      
IUEAO   vituperator (WebC7)                           induperator                      
IUEOA   Figueroa (TIG - in Chile)                     milquetoast (Milquetoast 1973)   
IUOAE   insupportable (WebC7)                         insupposable                     
IUOEA   immunotherapy (WebC7)                         circumcorneal                    
OAEIU   hypotrachelium (Web3)                         mycobacterium                    
OAEUI   pyrocatechuic (Web2)                          longaeuity (longevity 1621)      
OAIEU   containerful (BT)                             solacieus (solacious)            
OAIUE   portraiture (WebC7)                           ortanique                        
OAUEI   opaqueing (OED)                               contrauersi (sorely c1450)       
OAUIE   consanguine (WebC7)                           oraculize                        
OEAIU   overpainful (Web2)                            cometarium                       
OEAUI   overhauling (WebC7)                           overvaulting                     
OEIAU   Oeciacus (Web3), coeliacus (Web3 - coeliac)   obeiauns                         
OEIUA   proventricular (Web3)                         conventicular                    
OEUAI   conceptualism (WebC7)                         coequality                       
OEUIA   obsequial (Web3)                              orteguina                        
OIAEU   poplitaeus (Web3)                             omnigatherum                     
OIAUE   foliature (WebC5)                             consignature                     
OIEAU   moineau (Web2)                                cointreau                        
OIEUA   ovicellular Web3)                             coniecturall (conjectural 1597)  
OIUAE   continuable (Web2)                            orbiculate                       
OIUEA   solifugean (Web3)                             constituentary                   
OUAEI   outcapering (Web2)                            outwandering                     
OUAIE   tourmaline (WebC7)                            gourmandise                      
OUEAI   housemaid (WebC7)                             mousetail                        
OUEIA   volumetrically (WebC7)                        countercyclical                  
OUIAE   communicate (WebC7)                           occupiable                       
OUIEA   bountihead (Web2)                             outlinear                        
UAEIO   quaternion (WebC7)                            unattention                      
UAEOI   quatrefoil (WebC7)                            crustaceoid                      
UAIEO   unpraiseworthy (Web2)                         guarnimento (ray c1450)          
UAIOE   ultraviolet (WebC7)                           ungainsome                       
UAOEI   ultramodernism (Web2)                         unatmospheric                    
UAOIE   uvarovite (WebC7)                             unaccomplished                   
UEAIO   numeration (WebC7)                            putrefaction                     
UEAOI   unreasoning (WebC7)                           unseasoning                      
UEIAO   pulverizator (Web2)                           guesstimator                     
UEIOA   questionably (WebC7)                          unreciprocal                     
UEOAI   undemocratic (WebC7)                          undercoating                     
UEOIA   unmethodical (WebC70                          unrhetorical                     
UIAEO   quinaseptol (CDS)                             subitaneo (sudden)               
UIAOE   multianode (?), multiramose (Web2)            undiagnosed                      
UIEAO   quindecagon (WebC5)                           multimegaton (multi- 1958)       
UIEOA   unipersonal (Web2)                            multipersonal                    
UIOAE   unimportance (WebC7)                          undissolvable                    
UIOEA   undiscoverably (Web3)                         unicorneal                       
UOAEI   sulphophthaleins (Web2)                       burgomastership                  
UOAIE   unorganized (WebC7)                           sulphocyanide                    
UOEAI   suboceanic (WebC7)                            unoperating                      
UOEIA   uncongenial (WebC7)                           uncommercial                     
UOIAE   subordinate (WebC7)                           unsociable                       
UOIEA   unoriental (Web2)                             uncomplimentary                  

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