Design phase botched (5)
I believe the answer is:
shape
'design' is the definition.
(thesaurus)
'phase botched' is the wordplay.
'botched' indicates an anagram.
'phase' anagrammed gives 'SHAPE'.
(Other definitions for shape that I've seen before include "Form, figure" , "Heaps (anag.)" , "Good physical form" , "'Figure, outline (5)'" , "Form; mould" .)