The most common and most likely answer to this crossword clue is the 7 letter word IMMURED
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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 IMMURED mean?
IMMURED verb- To cloister, confine, imprison: to lock up behind walls.
- To put or bury within a wall.
- (of a growing crystal) To trap or capture (an impurity); chiefly in the participial adjective immured and gerund or gerundial noun immuring.
- Imprisoned or confined