One hat on husband following church party (7)
I believe the answer is:
ceilidh
'party' is the definition.
(I know that ceilidh is a type of party)
'one hat on husband following church' is the wordplay.
'one' becomes 'I' (Roman numeral).
'hat' becomes 'lid' (lid can informally mean a hat).
'on husband' becomes 'h' (I am not sure about the 'on' bit.).
'following' means one lot of letters go next to another.
'church' becomes 'CE' (abbreviation for Church of England).
'i'+'lid'+'h'='ilidh'
'ilidh' after 'ce' is 'CEILIDH'.
(Other definitions for ceilidh that I've seen before include "social gathering" , "Musical party" , "Gathering with Celtic folk music, singing and dancing" , "Celtic folk music event" , "Scottish singing and dancing event" .)