What is the longest word in English with only vowels?

The longest English word with only vowels is “euouae”, a medieval musical term.

📜 History: “Euouae” refers to a sequence of tones in Gregorian chant notation. It’s the longest word without consonants recorded in dictionaries.

🤔 Trivia: Another vowel-heavy word is “iouea”, which appears in dictionaries as a genus of sea sponges.