Further; extra (4)

I believe the answer is:

I believe this is a double definition.

'further' is the first definition.
(synonyms)

'extra' is the second definition.
(both can mean additional)

(Other definitions for more that I've seen before include "To a greater extent" , "Extra (for Sir Thomas?)" , "Greater quantity or number" , "Writer" , "author" .)

I've seen this clue in The Times.

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