What does the cryptic crossword clue "Bottom section of genuine Thermos twists (10)" mean?

The definition is "Bottom". The wordplay uses a hidden word. Hidden in "bottom section of genuiNE THERMOS Twists" The answer is NETHERMOST.

Bottom section of genuine Thermos twists (10)

Times Cryptic #29189 | 15 Across | 2025-03-28 flower