Hat a chap raised to father (6)
I believe the answer is:
panama
'hat' is the definition.
(I know that Panama is a type of hat)
'a chap raised to father' is the wordplay.
'chap' becomes 'man' (chap can mean a man).
'raised' says the letters should be written backwards (going up in a down clue).
'to' says to put letters next to each other (I've seen this in other clues).
'father' becomes 'pa' (pa can mean dad or father).
'a'+'man'='aman'
'aman' backwards is 'nama'.
'nama' put after 'pa' is 'PANAMA'.
(Other definitions for panama that I've seen before include "isthmus" , "country divided by boaters?" , "American canal or kind of hat" , "Criticise" , "Man's hat" .)