Spike's neat boy roughed up (7)
I believe the answer is:
bayonet
'spike's' is the definition.
(thesaurus)
'neat boy roughed up' is the wordplay.
'roughed up' is an anagram indicator.
'neat'+'boy'='neatboy'
'neatboy' with letters rearranged gives 'BAYONET'.
(Other definitions for bayonet that I've seen before include "Blade fixed to a rifle" , "Stabbing weapon" , "Pointed weapon" , "Rifle attachment" , "Knife fixed to the end of a rifle" .)