The most common and most likely answer to this crossword clue is the 11 letter word HIPPOCAMPUS
H
I
P
P
O
C
A
M
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S
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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 HIPPOCAMPUS mean?
HIPPOCAMPUS noun- A mythological creature with the front head and forelimbs of a horse and the rear of a dolphin.
- A part of the brain located inside the temporal lobe, consisting mainly of grey matter. It is a component of the limbic system and plays a role in memory and emotion.