Crossword Genius

Reporter's relatively hackneyed cover for The Observer (6)

Ross

I believe the answer is:

cornea

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'observer' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.

I can't explain the remainder of the clue.

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(Other definitions for cornea that I've seen before include "Transparent part of the coat of the eyeball" , "seen through by pupil" , "Membrane of the eye" , "Front covering of eye" , "Body part" .)

I've seen this clue in The Telegraph.
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