Five English Words That Are Utterly Unique
From dictionary.com
Syzygy (SIZ-ih-jee) noun
Amazingly, the only English word with three Ys also happens to describe a rare astronomical event involving three heavenly bodies. A syzygy is the alignment of three celestial bodies in a straight line, commonly the Earth, the Sun and the Moon.
Dreamt (DREMT) verb
A poet would appreciate how this past tense of dream possesses such a special quality -- the only verb in regular English usage to end with -mt. We hear from people constantly who swear there must be another term ending in -mt. No one has ever actually offered a second example, however. Perhaps it exists in a dream.
Tmesis (tuh-MEE-sis) noun
The next word is the opposite of the last. It is the sole term in the English language to begin with tm- and has an unusual meaning to match. Tmesis is the insertion of one or more words between the words that make up a compound phrase, as in “so” inserted in the middle of "whatever" to make “what-so-ever.”
Hydroxyzine (hi-DROK-suh-zeen) noun
Only one word in all of English has an X, Y, and Z in order. Hydroxyzine is also the only word on this list that you may have swallowed at some point. This medication, developed in the 1950s, can help calm you down, prevent sneezing, and impress you with unique linguistic qualities.
Queue (KYOO) noun
Our final word is more of a riddle: What is the only English term pronounced the same if you remove four letters? Before it meant “a line,” a queue referred to the tail of a beast in medieval pictures and designs. The unusual spelling owes its origin to French, like many words that look a little odd in English. Prior to the Frenchification of queue, Latin spelled it simply as coda. The duplication of U and E often feels like waiting in line: once you think you are almost there, the queue magically seems to repeat itself.