The missing word in the given text is "justice."
Thurgood Marshall stepped up to the Supreme Court.
As the first black justice ever,
He made fighting for rights his major endeavor.
Thurgood Marshall was indeed the first African American justice to serve on the United States Supreme Court. He was appointed by President Lyndon B. Johnson in 1967 and played a significant role in advancing civil rights through his work as a lawyer and later as a Supreme Court justice. His dedication to fighting for equality and justice has left a lasting impact on the legal landscape of the United States.