What does the cryptic crossword clue "Men to go back, always ending in retreat (4)" mean?

The definition is "retreat". The wordplay uses acrostic. last letters of "Men to go back," = NOOK; definition: "retreat" The answer is NOOK.

Men to go back, always ending in retreat (4)

Times Cryptic #28793 | 24 Across | 2023-12-22 flower