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Joan Rivers arrives for "Late Show With David Letterman" on Tuesday.

Singer Adele took home an Oscar in the best original song category Sunday night, but she also had to listen to host Seth MacFarlane joke about her weight. The jokes aren't over: On Wednesday night's "Late Night With David Letterman," comedian Joan Rivers poked fun at the singer's size as well.

"I met Adele! Has she been on the show?" Rivers asked Letterman, puffing out her cheeks and holding her arms far away from her body. When the audience booed, Rivers snapped, "Oh no! No! She's thin! Can we just talk to each other here?"

"What is her song, 'Rolling in the Deep'? She should add, 'Fried Chicken,'" Rivers cracked.

Rivers went on to say that Adele expressed concern about her live Oscars performance, saying, "My throat, my throat! I don't know if I can swallow."

"And I said, 'Oh yeah, you can swallow,'" Rivers said, again holding her arms out to indicate a large person.

Rivers is also being called upon by the Anti-Defamation League to apologize for a "vulgar and hideous" Holocaust joke she made about German-born model Heidi Klum.

On the E! show "Fashion Police" Monday, Rivers said, "The last time a German looked this hot was when they were pushing Jews into the ovens."

The ADL says in a press release that  the segment has been shown at least four times on the network and appeared briefly on YouTube.

"It is vulgar and offensive for anybody to use the death of six million Jews and millions of others in the Holocaust to make a joke, but this is especially true for someone who is Jewish and who proudly and publicly wears her Jewishness on her sleeve," the ADL said of Rivers.

At press time, "Fashion Police" had not responded to a request for comment.

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Joan Rivers

Comedian Joan Rivers is taking some heat for two Whitney Houston jokes that reportedly appear in her upcoming book, "I Hate Everyone ... Starting With Me."

The Village Voice reports that in a section on travel, Rivers writes: "I hate Houston ... it's crawling with bugs. Oh, wait, that's Whitney Houston; I'm sorry, my bad. (Can I just mention that Whitney looked fabulous at the Grammys?  She was in mahogany from head to toe.)"

Houston, 48, was found dead in her Beverly Hills, Calif. hotel bathtub on Feb. 11, the day before the Grammys.

The jokes shouldn't be a surprise to those who read the book's description on the website of publisher Penguin, which reads, "uncensored and totally uninhibited (Rivers gives) the best of her worst to First Ladies, closet cases, hypocrites, Hollywood, feminists, and overrated historical figures," and goes on to call the book an "honest, unabashedly hilarious love letter to the hater in all of us."

Readers of the Village Voice post were divided over whether Rivers' remark was too much, too soon.

"There's funny tasteless and there's just tasteless and unfortunately, this joke is in the latter category," wrote one reader.

Said another: "Joan Rivers is still funnier than most comedians half her age. Making tasteless jokes about celebrities is what she does. If you don't enjoy her, fine, but please don't try to say that all of a sudden she's crossed a line she never crossed before."

Back in February, in an interview with Andy Cohen on "Watch What Happens Live," Rivers said she's never regretted insulting anyone because her jokes are "never meant to be mean." She also said when singer Willie Nelson's daughter wrote her to say that a Rivers' joke about Nelson resulted in the girl being teased at school, she took that joke out of her act.

Also in February, Rivers was criticized by some for snarky remarks she made about Houston's wardrobe on the E! show "Fashion Police." According to Women's Wear Daily, Rivers said, "Am I sorry (Houston) died? Of course I am, for God’s sake." She also said "If Angelina Jolie died tomorrow, I would still say she was anorexic."

After Houston's death, Rivers tweeted, "Whitney Houston. What a sad tragedy — the end of the life of an incredible talent. RIP to an amazing singer and legend.”

Rivers' book will be published June 5.

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Bravo

"Fashion Police" queen Joan Rivers has never been shy about saying exactly what she thinks -- whether she's doing a comedy routine or judging the stars at a red-carpet event. And her words can sometimes be brutally honest.

But despite how her jokes or fashion critiques may come across as unnecessarily harsh to some, she told Andy Cohen on "Watch What Happens Live" Thursday night that her insults aren't meant to be mean or hurt anyone's feelings. And because of that, she doesn't really regret poking fun at celebs -- especially when they get her jokes.

For example, Rivers said she was the first to do fat jokes about Elizabeth Taylor.  Taylor's response, according to Rivers? "It doesn't bother me."

But there is one joke the comedian nuked from her act. Rivers said she used to poke fun of "country guy" Willie Nelson by saying "he wore a roach motel around his neck." When Rivers learned that the singer's then young daughter was getting teased at school because of it, the dig was immediately removed from her act. "I'm not there to make a little girl be unhappy," Rivers said. "But if you're making $25 million a movie and I don't like your dress, that's not tragic."

Cohen also asked the comedian whether she's been honored with the Kennedy Center Awards. Rivers' response? "Are you out of your mind?! Nobody ever recognizes me. No way!" When her host expressed shock, Rivers explained, "I'm too outrageous. And I don't play the game, and I say what I think, and I must've insulted everybody at one point."

See what else she had to say and what other celebs she pokes fun at:

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