Longest officially recognized place name is Taumatawhakatangihangakoauauotamateapokaiwhenuakitanatahu.
112
In Turkish, the bird we call a Turkey is called "Hindi" ("from India"). In India, it's called "Peru." In Arabic, the bird is called "Greek chicken"; in Greek it's called "French chicken"; and in French it's called "Indian chicken." The bird is indigenous to none of these places.
44
A group of ferrets is called a business.
6
A “butt” was a Medieval unit of measure for wine. Technically, a 'buttload' of wine is about 475 liters, or 126 gallons.
10
The word "impossible" dropped in use by 50% over the course of the 20th century
5
Floccinaucinihilipilification, the declaration of an item being useless, is the longest non-medical term in the English language.
125
The word "listen" contains the same letters as "silent."
135
Switching letters is called spoonerism. For example, saying "jag of Flapan", instead of "flag of Japan".
2