anagram
Concise Oxford English Dictionary © 2008 Oxford University Press:
anagram /ˈanəgram/
▶noun a word, phrase, or name formed by rearranging the letters of another, such as spar, formed from rasp.
– derivatives
anagrammatic adjective,
anagrammatical adjective
anagrammatize (or anagrammatise) verb.
anagrammatic adjective,
anagrammatical adjective
anagrammatize (or anagrammatise) verb.
– origin C16: from Fr. anagramme or mod. L. anagramma, from Gk ana- ‘back, anew’ + gramma ‘letter’.
'anagram' also found in these Oxford entries:

