The shortest word containing all five vowels exactly once is the six-letter EUNOIA, meaning alertness of mind an will (and also the title of a book by Canadian poet Christian Bok). However, it is not included in any major English dictionary. There are several seven-letter words containing all the vowels, including SEQUOIA, EULOGIA, MIAOUED, ADOULIE, EUCOSIA, EUNOMIA, EUTOPIA, MOINEAU, and DOULEIA. The relatively common French word OISEAU (meaning bird) contains all five vowels, once each.
The shortest word with the five vowels occurring in alphabetical order is AERIOUS (airy), which has seven letters. The longest such word is PHRAGELLIORHYNCHUS (a protozoan) with 18 letters. There are two seven-letter words in Portuguese that contain the five vowels in alphabetical order: ACEITOU and ALEIJOU.
SUOIDEA (the taxonomic group to which pigs belong) is the shortest word with the five vowels in reverse alphabetical order. The longest such word is PUNCTOSCHMIDTELLA (a crustacean).
http://www.fun-with-words.com/word_vowels.html
