What name did Beyoncé use for her alter ego in the 2008 album title?

Beyoncé used the name Sasha Fierce for the alter ego in her 2008 album title.

I Am... Sasha Fierce was released in November 2008 as Beyoncé’s third solo studio album. Its two-disc structure contrasted introspective songs under “I Am...” with more assertive, performance-driven songs under “Sasha Fierce.” Beyoncé described Sasha Fierce as a stage persona that helped her become more uninhibited during performances.

The album produced major singles including “If I Were a Boy,” “Halo,” “Diva,” and “Single Ladies (Put a Ring on It).” “Single Ladies” became especially associated with its sharply choreographed black-and-white music video.

The persona was not a separate recording artist or a legally distinct person. Beyoncé later said she no longer needed the alter ego and had effectively retired it. The title therefore describes an artistic concept within the album, not another singer.