Marcia Wallace, the woman behind the voice of The Simpsons' character Edna Krabappel, has died aged 70.
She played Bart Simpson's fourth-grade teacher – who chain-smoked, had a signature laugh ("Ha!") and sporadic relations with the school's hapless principal.
The show's executive producer, Al Jean, said Wallace would be sorely missed and that her character will be retired from the show.
"I was tremendously saddened to learn this morning of the passing of the brilliant and gracious Marcia Wallace. She was beloved by all at The Simpsons and we intend to retire her irreplaceable character," he said in a statement.
Staff had recently teased the idea of killing off a character on the show , but Jean said this was not related to Wallace.
"Earlier we had discussed a potential storyline in which a character passed away.
"This was not Marcia's Edna Krabappel. Marcia's passing is unrelated and again, a terrible loss for all who had the pleasure of knowing her."
Wallace featured in 177 episodes of the series and won an Emmy Award for her work in the 1992 episode, Bart the Lover.
Fellow voice actor, Yeardley Smith, who plays Lisa Simpson, sent out a heartfelt message on Twitter.
"Cheers to the hilarious, kind, fab Marcia Wallace, who has taken her leave of us. Heaven is now a much funnier place b/c of you, Marcia."
Wallace was diagnosed with breast cancer in 1985 and became a high-profile advocate for cancer awareness.
However, the cause of her death has not yet been confirmed.
Her career highlights include a wise-cracking receptionist on CBS's The Bob Newhart Show and appearances on Murphy Brown.
She also featured on episodes of Bewitched, The Brady Bunch, Murder She Wrote and Full House.