Vowel

A vowel is any letter in the alphabet other than a consonant. The only written vowels in the English language are "a", "e", "i", "o", "u", and sometimes "y" depending on the context. It is nearly impossible to make a pronounceable word without using at least one vowel, though onomatapoeatic "words" such as "hmmm", "shhhh", and "brrr" have been used as a counterargument to this claim.

Some languages, such as Welsh and the Slavic languages Polish and Czech, have words consisting of consonants only.