It works like a charm (8)
I believe the answer is:
talisman
'it works like a charm' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for talisman that I've seen before include "Mascot" , "Liam, Stan has charm." , "Object bringing luck" , "Good luck token" , "Stone thought to have magical powers" .)