The most common and most likely answer to this crossword clue is the 7 letter word PLACOID
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The straight part
We know that "resembling shark scales" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case resembling shark scales = placoid.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 PLACOID mean?
PLACOID noun- Such a scale
- Any fish having placoid scales, such as the sharks
- Platelike; having irregular, platelike, bony scales, often bearing spines; pertaining to the placoid fish