Aide contrived plan (4)
I believe the answer is:
idea
'plan' is the definition.
(thesaurus)
'aide contrived' is the wordplay.
'contrived' indicates anagramming the letters.
'aide' with letters rearranged gives 'IDEA'.
(Other definitions for idea that I've seen before include "Mental impression" , "a wheeze" , "Suggestion" , "Proposal" , "Plato's Form is" .)