Vowel-Rich Words (and Words With No Vowels at All)

Why vowels matter in puzzles

English has only five standard vowel letters, and almost every word uses at least one. Finding out which vowels a word contains, and roughly where, eliminates more candidates per letter than most consonants can. See information theory in word games for why.

Four-letter words with three vowels

AQUA
AREA
ARIA
AURA
EASE
EURO
IDEA
IOTA
OBOE
UREA

Words like these are favorites of crossword constructors, because vowel-heavy short words make it easier to fill a grid. If you solve crosswords, they are worth knowing on sight.

Five-letter words with four vowels

ADIEU
AUDIO
QUEUE
EERIE
AERIE
AIOLI
OUIJA

QUEUE is the classic oddity: one consonant followed by four vowels, and pronounced like its first letter alone.

Words containing all five vowels

Word	Note
SEQUOIA	Seven letters, all five vowels — among the shortest common English words to manage it.
EDUCATION	Each vowel exactly once.
DIALOGUE	Each vowel exactly once, in eight letters.
EQUATION	Each vowel exactly once, in eight letters.
FACETIOUS	All five vowels in alphabetical order.
ABSTEMIOUS	Also in alphabetical order.
PNEUMONIA	Plus a silent P at the start.
HOUSEMAID	A compound that happens to collect the set.

When Y is the vowel

Y acts as a vowel whenever it carries the vowel sound of a syllable. These common words contain none of A, E, I, O, U:

BY
MY
FLY
SKY
TRY
WHY
GYM
MYTH
LYNX
HYMN
CRYPT
NYMPH
RHYTHM

Using vowel-rich words well

They are scouts, not answers. A vowel-heavy guess is for gathering information. The actual answer is usually a more ordinary mix.
Do not neglect consonants. Knowing a word has A and E still leaves thousands of options; R, S, T, L and N narrow it.
Watch for repeated vowels. EERIE and GEESE each use E more than once. A confirmed vowel can still appear again.