Wash resin out (5)
I believe the answer is:
rinse
'wash' is the definition.
(I know that rinse is a type of wash)
'resin out' is the wordplay.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'resin' is an anagram of 'RINSE'.
(Other definitions for rinse that I've seen before include "Wash in clean water" , "Hair preparation" , "Flush" , "Wash off surface dirt" , "Sluice" .)