The most common and most likely answer to this crossword clue is the 9 letter word HARBOURED
I've seen this crossword clue in Independent
H
A
R
B
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D
More clues leading to the result HARBOURED
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The straight part
We know that "Protected" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case protected = harboured.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 HARBOURED mean?
HARBOURED verb- To provide a harbor or safe place for.
- To take refuge or shelter in a protected expanse of water.
- To drive (a hunted stag) to covert.
- To hold or persistently entertain in one's thoughts or mind.