"Of all the nicknames Trump has given people -- I don't know what to say -- Sloppy Steve fits," Kimmel says.
Released Friday, the book paints a messy, unflattering portrait of the Trump family as told by people who work with him and for him. And in typical Trump fashion, POTUS took to Twitter to lash out at both the author of the novel and former chief strategist Steve Bannon, who was interviewed for the book.
"I authorized zero access to White House (actually turned him down many times) for author of phony book!" Trump tweeted just before the book's release. "I never spoke to him for book. Full of lies, misrepresentations and sources that don't exist. Look at this guy's past and watch what happens to him and Sloppy Steve!"
"Now, Sloppy Steve is Trump's new nickname for Steve Bannon, and I have to admit, it's a good one," the comedian said on "Jimmy Kimmel Live" Friday night. "Of all the nicknames Trump has given people -- I don't know what to say -- Sloppy Steve fits."
Kimmel noted that the president has already used the nickname twice since making it up on Thursday evening, referencing a Friday morning tweet from POTUS that read, "The Mercer family recently dumped the leaker known as Sloppy Steve Bannon. Smart!"
"I like when he comes up with a nickname and then acts like it was a thing," Kimmel joked. "He wasn't known as Sloppy Steve Bannon; you named him that yesterday."
Wolff appeared on the "Today" show Friday morning to thank Trump for calling so much attention to "Fire and Fury" by trying to stop it from being published. He also said that "100 percent of the people" he interviewed questioned Trump's intelligence and fitness for office.
"So that's like almost all of them, right?" Kimmel asked. "I'm looking forward to a few weeks from now when Trump starts taking credit for how great sales of the book were: 'People love my book! It's fantastic!'"