Get grime off kitchen item (3,5)
I believe the answer is:
egg timer
'kitchen item' is the definition.
(I've seen this before)
'get grime off' is the wordplay.
'off' is an anagram indicator.
'get'+'grime'='getgrime'
'getgrime' is an anagram of 'EGG TIMER'.
(Other definitions for egg timer that I've seen before include "One may be set to, say, three minutes" , "Meter gig for measuring the boiling of hen-fruit" , "Small kitchen sandglass" , "device for boiler" , "Kitchen item" .)