Those letters can be used to spell "barbarian".
Librarian is a 9 letter word that has letters BRAIN in it.
there is no 9 letter word starting with e and using all of the letters. but the word unscrambled is FORGETFUL.
evergreen
tyrannous
The nine letter word is riverbank.
The nine letter word is renewable.
There is no 9 letter word, 4th letter r that can be made from those letters.
A nine letter word using those letters is boomerang.
recapture
escalator
The answer is extricate.
Forgetful.