The most common and most likely answer to this crossword clue is the 7 letter word HOGBACK
I've seen this crossword clue in The Daily Telegraph
H
O
G
B
A
C
K
More clues leading to the result HOGBACK
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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 HOGBACK mean?
HOGBACK noun- A sharp steep-sided ridge formed by the erosion of tilting strata
- A hogframe.
- A Viking grave marker taking the form of a recumbent monument, generally with a curved (hogbacked) ridge and outwardly curved sides.