What does the cryptic crossword clue "Woman worked with Hitler, the butt of many jokes (6,2,3)" mean?

The wordplay uses an anagram. anagram of WOMAN + HITLER, = MOTHERINLAW The answer is MOTHERINLAW.

Woman worked with Hitler, the butt of many jokes (6,2,3)

Daily Mail Cryptic #16616 | 19 Across | 2021-07-09 flower