1. “Bookkeeper” is the only word that has three consecutive doubled letters.
2. The two longest words with only one of the six vowels including y are the 15-letter defenselessness and respectlessness.
3. “Forty” is the only number which has its letters in alphabetical order. “One” is the only number with its letters in reverse alphabetical order.
4. The superlatively long word honorificabilitudinitatibus (27 letters) alternates consonants and vowels.
5. Antidisestablishmentarianism listed in the Oxford English Dictionary, was considered the longest English word for quite a long time, but today the medical term pneumonoultramicroscopicsilicovolcanoconiosis is usually considered to have the title, despite the fact that it was coined to provide an answer to the question ‘What is the longest English word?’.
6. “The sixth sick sheik’s sixth sheep’s sick” is said to be the toughest tongue twister in English.
7. There is only one common word in English that has five vowels in a row: queueing.
8. The two longest words with only one of the six vowels including y are the 15-letter defenselessness and respectlessness.
9. “Asthma” and “isthmi” are the only six-letter words that begin and end with a vowel and have no other vowels between.
10 “Rhythms” is the longest English word without the normal vowels, a, e, i, o, or u.