What does the cryptic crossword clue "Disobedience provoked it in union's board (15)" mean?

The wordplay uses an anagram. anagram of IT + IN + UNION'S + BOARD = INSUBORDINATION The answer is INSUBORDINATION.

Disobedience provoked it in union's board (15)

Daily Mail Cryptic #17500 | 7 Down | 2024-11-29 flower