Keitha is a feminine form of the name Keith, which originated as a Scottish surname derived from the place name Keith in East Lothian. The place name itself possibly comes from the Celtic root *kayto- meaning "wood." The surname Keith was carried by a prominent Scottish noble family, the Clan Keith, whose history dates back to the 12th century. Sir William de Keith was granted lands in East Lothian, and later members served as Earls Marischal of Scotland. As a given name, Keith began to be used in the 19th century and became widely popular in the 20th century across English-speaking countries. The feminine form Keitha emerged as a way to feminize the name, likely gaining some use in the 20th century, though it never achieved the same popularity as its male counterpart. It remains a rare given name in modern times.