First of lads in bar is the woman's bookmaker! (9)
I believe the answer is:
publisher
'bookmaker' is the definition.
(thesaurus)
'first of lads in bar is the woman's' is the wordplay.
'first of' indicates taking the first letters.
'in' is an insertion indicator.
'bar' becomes 'pub' (I've seen this before**).
'the woman's' becomes 'her'.
The initial letter of 'lads' is 'l'.
'pub'+'is'='pubis'
'l' going inside 'pubis' is 'publis'.
'publis'+'her'='PUBLISHER'
(Other definitions for publisher that I've seen before include "Man with many titles" , "bookmaker!" , "Eg Jonathan Cape or Hamish Hamilton" , "One utters volumes" , "Issuer of books, music, etc" .)