Outcome of strange rustle (6)
I believe the answer is:
result
'outcome' is the definition.
(I know that outcome can be written as result)
'strange rustle' is the wordplay.
'strange' indicates anagramming the letters.
'rustle' is an anagram of 'RESULT'.
'of' acts as a link.
(Other definitions for result that I've seen before include "Effect of lustre" , "End - issue" , "'Outcome, consequence (6)'" , "Final outcome" , "Final score" .)