Brilliance in golf shown by little swine! (7)
I believe the answer is:
glitter
'brilliance' is the definition.
(thesaurus)
'golf shown by little swine' is the wordplay.
'golf' becomes 'g' (phonetic alphabet: alpha, bravo, charlie etc.).
'shown by' means one lot of letters go next to another.
'little swine' becomes 'litter' (litter could refer to a litter of piglets).
'g'+'litter'='GLITTER'
'in' acts as a link.
(Other definitions for glitter that I've seen before include "Shine brightly, coldly" , "Twinkle" , "Sparkle on cards" , "Gleam" , "Flash" .)