Lydia (disambiguation)

Lydia is a given name that can refer to:
 * Lydia Cooden, a Gryffindor student at Hogwarts School of Witchcraft and Wizardry in the 1990s
 * Lydia Fry, a Muggle media personality

Behind the scenes
Real-world individuals with the given name Bill include:
 * Lydia Andrew, an actress who voiced the mermaid in the video game adaptation of Harry Potter and the Goblet of Fire