Boy, by complete coincidence, not female (4)

I believe the answer is:

luke

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'boy' is the definition.

I cannot understand how the remainder of the clue works.

(Other definitions for luke that I've seen before include "Physician gospeller" , "Traditionally the author of the third Gospel" , "One of the four Evangelists" , "One of the Apostles" , "Third NT book" .)

I've seen this clue in The Guardian.

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