The most common and most likely answer to this crossword clue is the 10 letter word DIPLODOCUS
I've seen this crossword clue in The Times
D
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P
L
O
D
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C
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S
More clues leading to the result DIPLODOCUS
- Dinosaur's decline complete in the vicinity
- Prehistoric creature complete in hollow place
- Lower position defining party, a dinosaur
- Go under: so could swimming dinosaur
- One had a huge amount of meat after I’d served up nasty cold soup!
- Old copper goes after two policemen start to suspect one hasn’t been seen in ages
Buddy explains!
The straight part
We know that "Prehistoric creature" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case prehistoric creature = diplodocus.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 DIPLODOCUS mean?
DIPLODOCUS noun- Any of several herbivorous sauropod dinosaurs, of the genus Diplodocus, known as fossils from the late Jurassic in North America.