English hairstyle I'd adopted is what protects us? (9)

I believe the answer is:

epidermis

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But I can't explain it at all! Could you help me understand?

(Other definitions for epidermis that I've seen before include "Outermost layer" , "Protective covering" , "Outer layer of skin" , "Surface of the skin" .)

I've seen this clue in The Times.

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