Oprah Winfrey condemned fake news and disinformation in a commencement speech to graduates of the University of Southern California's Annenberg School for Communication and Journalism on Friday, imploring students to conquer the "hysteria" that grips national politics and "strike down deceit" wherever they see it.

Winfrey deplored the ways the internet was being used to "erode trust in our institutions, enter fear in our elections and wreak havoc on our infrastructure" — a veiled swipe at Russia-linked propaganda and the social media platforms, like Facebook, on which it spread during the 2016 presidential election.

The modern digital ecosystem, Winfrey said, "enables misinformation to run rampant, attention spans to run short and false stories from phony sites to run circles around major news outlets."

Winfrey's commencement address, by turns galvanizing and lighthearted, recalled the speech she delivered at the Golden Globe Awards ceremony in January — impassioned remarks about racial injustice, gender inequality and the #MeToo movement that stirred speculation about her White House ambitions.

She nodded to that speculation in her address on Friday, joking that she hesitated to tell the USC graduates about the importance of voting and civic participation because "the rumors from my last big speech have finally died down."

But she nonetheless waded into politics, calling on the graduates to "overcome the sniping at one another, the trolling, the mean-spirited partisanship on both sides of the aisle, the divisiveness, the injustices, the out-and-out hatred."

"If they go low — thank you, Michelle Obama — we go to the polls," she said of elected officials, paraphrasing former first lady Michelle Obama’s oft-quoted words at the 2016 Democratic National Convention. "People died for that right. I think about it every time I cast a vote, so don’t let their sacrifice be in vain."

Winfrey, 64, did not directly address President Donald Trump, and she made it explicitly clear that the young journalists seated in the auditorium must "use what you've learned to challenge the left, challenge the right, and the center."

The world-famous media mogul was introduced by Willow Bay, the dean of the Annenberg school and the wife of Disney CEO Robert Iger. Winfrey, who is widely described as Iger's good friend, reportedly pushed him to run for president in 2020 before he decided against it.