Noblewoman in pub with one's son (8)
I believe the answer is:
baroness
'noblewoman' is the definition.
(baroness is a kind of noblewoman)
'pub with one's son' is the wordplay.
'pub' becomes 'bar' (I've seen this before).
'with' says to put letters next to each other.
'son' becomes 's'.
'bar'+'ones'+'s'='BARONESS'
'in' is the link.
(Other definitions for baroness that I've seen before include "Aristocrat" , "Noblewoman" , "Thatcher possibly" , "Lady peer" , "Woman life-peer" .)