T'Keyah Crystal Keymáh (born Crystal Walker) is an American actress and singer. In addition to her status as an original cast member of the Fox sketch comedy series In Living Color (1990–1994), she is also known for her roles as Erica Lucas on the CBS sitcom Cosby (1996–2000), and as Tanya Baxter on the Disney Channel sitcom That's So Raven (2003–2005). 

Since the age of three, she has enjoyed entertaining her family – singing, dancing, and reciting original poems and stories. She wrote her first play and her first song in elementary school. She performed with Ali LeRoi and Lance Crouther in the Mary Wong Comedy Group in high school, before she enrolled in Florida A&M University (FAMU) at the School of Business and Industry. Her brother is Commander of the DC US Army National Guard, Major General William J. Walker.

During college and after graduating from FAMU, Keymáh taught theater, dance, and mime. She has also done many theater performances, and produced and directed films.

One of the original cast members of Fox Television's Emmy winning variety show, In Living Color, for five seasons Keymáh played a number of characters, including Cryssy, the central character of her self written signature piece, "In Black World". She also sang and danced on the show.

After In Living Color, she played contractor Scotti Decker in On Our Own; played comedy show writer Denise Everett in The Show; and provided the voices for Roz, Shavonne, Aki, Mrs. LaSalle, and many others in Waynehead. For four years, Keymáh was a series regular on Cosby, where she played flight attendant-lawyer-pastry chef-teacher Erica Lucas Hall. Following Cosby, she appeared for three seasons on the Disney series That's So Raven as Raven's mother, Tanya Baxter. In season four her character was written out of the plot so that Keymáh could care for her ailing grandmother.

Keymáh co-wrote and co-starred in a two-person stage show with music, called Sellout!?!, with fellow FAMU alumnus Bryan C. Jones, who was also one of the many guests to appear in her hit variety show T'Keyah Live! They did the first workshop presentation of Sellout!?! at FAMU.

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