Poet and Literary Icon Nikki Giovanni Dies at 81 / When Nikki Giovanni Was Young, Brilliant and Unafraid / Nikki Giovanni, "Princess of Black Poetry," Dies at 81 / Poet, Writer, and Activist Nikki Giovanni Dies at 81 / Black arts literary icon Nikki Giovanni dies at 81 / Poet Nikki Giovanni, 81 / Nikki Giovanni, Poet Who Wrote of Black Joy, Dies at 81