Tidy in one attempt (4)
I believe the answer is:
neat
'tidy' is the definition.
(similar in meaning)
'in one attempt' is the wordplay.
'in' indicates a hidden word.
'NEAT' can be found hidden inside 'one attempt'.
(Other definitions for neat that I've seen before include "without ice?" , "well-kept" , "As whisky may be" , "Finished" , "Bovine animal" .)