LONDON — If Vicki Momberg had only unleashed a high-volume tirade at the South African police officers, video of it would have been of mere passing interest. But her repeated use of a racial slur — unfamiliar to most Americans, but explosive in South Africa — made her notorious, and led to demands to make her an example.

On Wednesday, Ms. Momberg, a white woman, became the first person in South Africa to be sent to prison for using racist language against someone, according to prosecutors and legal experts. Specifically, she hurled the term “kaffir,” considered the most offensive racial slur in South Africa — so radioactive socially that it is often referred to as “the k-word.”

The 2016 viral video of her outburst at police officers who responded to her report of thieves breaking into her car set off a national furor, and made Ms. Momberg a symbol of the racism that persists a generation after the collapse of apartheid.

Partly because of that video, viewed repeatedly on social media and news sites, the parliament may take up a bill that would make prosecution for hate speech more common.