What does the cryptic crossword clue "In pouring rain, get off toboggan? (6)" mean?

The wordplay uses a charade (building blocks). DE (synonym="DE") + LUGE (synonym="”toboggan”") = DELUGE The answer is DELUGE.

In pouring rain, get off toboggan? (6)

Guardian Cryptic #29519 | 28 Across | 2024-10-21 flower