Adele Slathered in Fat Jokes ... By Joan Rivers

3/7/2013 12:01 AM PST BY TMZ STAFF

Adele is UNDER ATTACK ...  getting blasted with fat jokes by a major celebrity looking to pick a fight ... and it was all caught on tape.

So who's the person hurling all the hatred?? It's Joan Rivers ... DUH ... didn't you read the headline?

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