Georgia was Georgia O'Keeffe’s first name in her full name, Georgia Totto O'Keeffe.
She was named Georgia Totto O'Keeffe at birth. “Totto” was her middle name, inherited from her maternal grandfather, George Victor Totto. O'Keeffe generally used Georgia as her public and professional name.
The artist became famous simply as Georgia O'Keeffe, a name now strongly associated with American modernism. Her reputation rests on paintings of enlarged flowers, New York buildings, New Mexico landscapes, animal bones, and abstract forms.
This question distinguishes a name detail from a title or nickname. O'Keeffe did not use “Totto O'Keeffe” as her usual professional identity, although the middle name appears in biographical records and reference works.