NEW YORK • Pause and think - should Kendrick Lamar stop a concert when a woman, among fans he invites on stage, sings a controversial word in lyrics that he himself has written?

On Sunday, the American music star and Pulitzer prize winner was upset when the white fan rapped the "n-word" from his 2012 hit M.A.A.D City.

The woman, who gave her name as Delaney, was one of several fans called on stage to perform the song at the Hangout Festival in Alabama.

But she failed to self-censor and repeated the "n-word" from the lyrics several times.

The word, while co-opted by black artists, remains the most derogatory term in the United States to refer to AfricanAmericans. Uttering it is a taboo for white people.

"Wait, wait, wait, wait, wait," said Lamar, 30, who comes from the historically deprived Los Angeles community of Compton, cutting her off and stopping the music.

"Am I not cool enough for you? What's up, bro?" Delaney said.

"You gotta bleep one single word though," Lamar replied.

As realisation dawned, she apologised, saying: "Oh, I'm sorry. Did I do it?"

He said: "Yeah, you did it."

He asked the audience whether she should remain on stage. They yelled back no, but Billboard magazine reported that he allowed her to perform the song again.

The incident provoked a storm of reactions on social media, spotlighting America's continuing struggle with racism and the controversy surrounding the word.

But while many commentators approved of Lamar's decision to cut off his fan, others were scathing.

"This is such a joke. If you feel so disrespected by someone rapping the words to the song you wrote... then don't write the lyrics," a Twitter user pointed out.

AGENCE FRANCE-PRESSE