Roguish, yet like an angel? (4)

I believe the answer is:

arch

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'roguish' is the definition.
(I've seen this before)

I can't explain the remainder of the clue.

(Other definitions for arch that I've seen before include "Prefix meaning chief - maybe an angel" , "Curved bony structure in the foot" , "Cunning; playful" , "Curvature" , "Curve of a bridge" .)

I've seen this clue in the Evening Standard.

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