Letter bank

A letter bank is a relative of the anagram where all the letters of one word can be used as many times as desired to make a new word or phrase. For example, IMPS is a bank of MISSISSIPPI and SPROUT is a bank of SUPPORT OUR TROOPS. As a convention, the bank should have no repeat letters within itself.
The term was coined by Will Shortz, whose first letter bank appeared in his 1979 book, "Brain Games". In 1980, Shortz introduced letter banks to the National Puzzlers' League, in the form of a contest puzzle. In 1981, the letter bank was announced an official puzzle type in the NPL’s magazine "The Enigma".
Letter banks are the basis for the word game Alpha Blitz.