A broad smile arrested by head's fury (9)
I believe the answer is:
'fury' is the definition.
(fury is being very angry)
'a broad smile arrested by head's' is the wordplay.
'broad smile' becomes 'grin' (I've seen this in another clue).
'arrested by' is an insertion indicator (I've seen this in other clues).
'head' becomes 'ness' (ness is a headland).
'grin' going into 'ness' is 'ngriness'.
(Another definition for angriness that I've seen is " wrath".)