What does the cryptic crossword clue "Old boxer maybe, one in the pulpit? (9)" mean?

The wordplay uses a charade (building blocks). EX (synonym="‘old’") + POUNDER (synonym="‘boxer maybe’") = EXPOUNDER The answer is EXPOUNDER.

Old boxer maybe, one in the pulpit? (9)

Guardian Cryptic #29537 | 19 Across | 2024-11-11 flower