Boss to lead old lady around area (3,6)
I believe the answer is:
top banana
'boss' is the definition.
(top banana means a boss or leader)
'to lead old lady around area' is the wordplay.
'lead' becomes 'Pb' (Pb is the chemical symbol for lead).
'old lady' becomes 'nana' ().
'around' shows that the letters should be reversed in order.
'area' becomes 'a' (maths abbreviation).
'nana' written backwards gives 'anan'.
'to'+'pb'+'anan'+'a'='TOP BANANA'
(Other definitions for top banana that I've seen before include "Best of the bunch!" , "figurehead?" , "Most important person in group (informal)" , "Star entertainer" , "leader" .)