Correct a method immediately (5,4)
I believe the answer is:
right away
'immediately' is the definition.
(synonyms)
'correct a method' is the wordplay.
'correct' becomes 'right' (right can mean correct).
'method' becomes 'way' (way of doing something).
'right'+'a'+'way'='RIGHT AWAY'
(Other definitions for right away that I've seen before include "Immediately" , "This very minute, without delay" , "This instant, without delay" , "in no time" , "without hesitation" .)