The most common and most likely answer to this crossword clue is the 7 letter word MORTISE
I've seen this crossword clue in Independent
M
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T
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More clues leading to the result MORTISE
Buddy explains!
The straight part
We know that "Sort of lock" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sort of lock = mortise.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 MORTISE mean?
MORTISE noun- A hole that is made to receive a tenon so as to form a joint.
- Stability; power of adhesion.
- To cut a mortise in.
- To join by a mortise and tenon.
- To adjust the horizontal space between selected pairs of letters; to kern.