Waste time changing filter (6)

I believe the answer is:

trifle

'waste time' is the definition.
(thesaurus)

'changing filter' is the wordplay.
'changing' indicates anagramming the letters.
'filter' is an anagram of 'TRIFLE'.

(Other definitions for trifle that I've seen before include "Not much" , "Cold dessert" , "Filter (anag.)" , "Sweet - little thing" , "Act foolishly" .)

I've seen this clue in the Sydney Morning Herald.

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