A Metamorphmagus is a kind of a
witch or a
wizard in the
Harry Potter book series by
J.K. Rowling.
Warning! The following text might contain
spoilers from the Harry Potter series!
In the Harry Potter series, a metamorphmagus is a witch or wizard who can change his or her appearance by thought.
This quality is very rare, but also very useful. A person who an change his appearance can easily disguise himself.
As of the end of the fifth book in the series, the only known metamorphmagus is Nymphadora Tonks, who is an Auror (a person who fights evil for the Ministry of Magic) and a member in the Order of the Phoenix, a group of people led by Albus Dumbledore who fight Voldemort and the Death Eaters. In both jobs the fact she is a metamorphmagus is very useful.
Though Tonks is the only known metamorphmagus, certain Harry Potter fans think also Luna Lovegood is a metamorphmagus, which would explain why Harry hasn't met her before the fifth book.