The most common and most likely answer to this crossword clue is the 9 letter word GLOWWORMS
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The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GLOWWORMS mean?
GLOWWORMS noun- The larva or wingless grub-like female of a beetle from the families Phengodidae or Lampyridae that gives out a green light from its abdomen.
- A carnivorous gnat larva in the keroplatid genus Arachnocampa that spins threads to capture insects attracted by its glow.