Maledictus

A Maledictus was an individual whose blood was cursed, eventually leading to them turning into a beast.

Known Maledictus

 * Nagini

Etymology

 * Mal- is a prefix of Latin origin meaning "bad", "wrongful", or "ill". Dictus in Latin means "spoken".
 * Roughly translated, Maledictus could mean "spoken ill of" or "cursed."
 * A malediction is a magical word or phrase used with the intention to cause harm, aka a curse.

Behind the scenes

 * Nagini's human form was the first time a Maledictus was mentioned in the wizarding world franchise, though blood-related curses were mentioned before with the case of Astoria Malfoy.
 * Werewolf is not considered a Maledictus.
 * It's unknown if a Muggle can carry the Maledictus curse.

Notes and references
Maledictus Maledictus Маледиктус