Fun With Words. Overnumerousnesses, eighteen letters long, is the longest English word that consists of only letters that lack ascenders, descenders, and dots in lower case.
Honorificabilitudinitatibus, 27 letters long, is the longest English word consisting strictly of alterating consonants and vowels.
Euouae, six letters long, is the longest English word consisting only of vowels, and, also, the English word with the most consecutive vowels.