Writer holding Underground up for one making her first appearance (9)
I believe the answer is:
debutante
'one making her first appearance' is the definition.
'writer holding underground up' is the wordplay.
'writer' becomes 'dante' (Dante is an example**).
'holding' means one lot of letters goes inside another.
'underground' becomes 'tube' ('tube' can be a synonym of 'underground').
'up' shows that the letters should be reversed in order (in down clue: letters go upwards).
'tube' backwards is 'ebut'.
'dante' going around 'ebut' is 'DEBUTANTE'.
'for' is the link.
(Other definitions for debutante that I've seen before include "young lady coming out" , "one about to come out" , "socialite" , "girl coming out" , "eligible young lady?" .)