Like this new boy (3)
I believe the answer is:
son
'boy' is the definition.
(male child)
'like this new' is the wordplay.
'like this' becomes 'so' ('like so').
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'so'+'n'='SON'
(Other definitions for son that I've seen before include "Native" , "Young boy" , "A relative" , "Express paper" , "Male child" .)