To a greater extent (4)
'to a greater extent' is the definition.
(synonyms)
This is all the clue.
(Other definitions for more that I've seen before include "author" , "Additional or larger amount" , "Writer" , "See 9" , "A greater amount" .)
'to a greater extent' is the definition.
(I've seen this in another clue)
This is the entire clue.