Horn-wearer's bird dropping round to have lunch and dinner, initially (7)

I believe the answer is:

cuckold

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'horn-wearer's' is the definition.
(a cuckold is figuratively said to wear horns)

I cannot understand how the rest of the clue works.

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(Other definitions for cuckold that I've seen before include "Man with an unfaithful wife" , "fool of a husband" , "Man whos wife is cheating on him?" , "One cheated" , "Betrayed husband" .)

I've seen this clue in The Guardian.

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