Additional to my recent comments on the longest word without a vowel .....
Words without vowels
A large number of Modern English words replace the 'ee' or 'eye' sound with the letter Y, such as try, sky, why, gym, hymn, lynx, myth, myrrh, pygmy, flyby, and syzygy. The longest such word in common use is rhythms, and the longest such word in Modern English is the obsolete 17th-century word symphysy. (If archaic words and spellings are considered, there are many more, the longest perhaps being twyndyllyngs, the plural of twyndyllyng.)
In the computer game The 7th Guest, one of the puzzles involves a vowelless sentence,
Shy gypsy slyly spryly tryst by my crypt.