#FireColbert is on fire.

Talk show host Stephen Colbert is taking serious heat on social media for a vulgar joke he made about President Donald Trump that many fans are calling "homophobic."

The "Late Show" star sounded off on Trump during his opening monologue Monday night, criticizing Trump for abruptly ending an interview with CBS News' "Face the Nation" host John Dickerson.

"Sir, you attract more skinheads than free Rogaine," Colbert said during his profranity-laced rant, which was bleeped during the telecast. "You have more people marching against you than cancer. You talk like a sign language gorilla that got hit in the head. In fact, the only thing your mouth is good for is being Vladimir Putin's c--k holster."

Fans immediately took issue with Colbert's final joke, with some calling the comedian homophobic, and demanding CBS fire him.

A rep for CBS and "Late Show" did not immediately return Fox News' request for comment.

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This isn't the first time viewers have gone on social media demanding Colbert's ouster. In 2014, a #CancelColbert hashtag was started after the host (on Comedy Central with "The Colbert Report" at that point) joked "I am willing to show #Asian community I care by introducing the Ching-Chong Ding-Dong Foundation for Sensitivity to Orientals or Whatever," in a sketch about Washington Redskins' owner Daniel Snyder's pro-Native American charity.

The hashtag campaign began when the show's Twitter account posted the joke without the context.

Colbert has seen a ratings resurgence since he started regularly roasting the president. After languishing in second place since he took over "The Late Show" for David Letterman, his show has been the No. 1 talk show on late night TV for 13 weeks running.