The most common and most likely answer to this crossword clue is the 8 letter word YARMULKE
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More clues leading to the result YARMULKE
- Mary adjusted Luke’s untidy skullcap
- Mary and Luke interpreted sign of religious devotion
- Version of Mary Luke redrafted showing Jewish garb
- Possibly gun concealed by king in Christmas cap
- Luke and Mary made to cover heads
- Cap distilled murky ale
- Short story–King wearing shoe and cap
- Sees this could disguise asylum seeker
- Murky ale is off — it may go to someone’s head
Buddy explains!

The straight part
We know that "cap" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cap = yarmulke.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 YARMULKE mean?
YARMULKE noun- A skullcap worn by religious Jewish males (especially during prayer).