Speak to daughter wearing a frock (7)
I believe the answer is:
address
'speak to' is the definition.
('address' can be a synonym of 'speak to')
'daughter wearing a frock' is the wordplay.
'daughter' becomes 'd'.
'wearing' means one lot of letters goes inside another.
'frock' becomes 'dress' ('dress' can be a synonym of 'frock').
'a'+'dress'='adress'
'd' going within 'adress' is 'ADDRESS'.
(Other definitions for address that I've seen before include "Look at" , "One's designated location" , "Place where someone lives" , "particular house" , "Speak to the residence" .)