The most common and most likely answer to this crossword clue is the 8 letter word DIPTERAN
I've seen this crossword clue in The Guardian
D
I
P
T
E
R
A
N
More clues leading to the result DIPTERAN
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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 DIPTERAN mean?
DIPTERAN noun- An insect of the large order Diptera; a fly.
- Relating to or denoting dipterans.