What does the cryptic crossword clue "Marine creature managed to turn over by itself almost (7)" mean?

The definition is "almost". The wordplay uses a reversal. RAN (reversal="managed") + WHAL (synonym="WHAL") = NARWHAL The answer is NARWHAL.

Marine creature managed to turn over by itself almost (7)

Guardian Cryptic #29608 | 27 Across | 2025-02-03 flower