Supporting entry of Minister in ceremony (4)
I believe the answer is:
form
'ceremony' is the definition.
(form is a kind of ceremony)
'supporting entry of minister' is the wordplay.
'supporting' becomes 'for' (**).
'entry of' says to take the initial letters.
The first letter of 'minister' is 'm'.
'for'+'m'='FORM'
'in' acts as a link.
(Other definitions for form that I've seen before include "Home of a hare" , "Acceptable conduct" , "Printed document with spaces to write" , "Seat" , "Part of school" .)