Drive mad in huge complex around noon (7)
I believe the answer is:
unhinge
'drive mad' is the definition.
(thesaurus)
'in huge complex around noon' is the wordplay.
'complex' indicates anagramming the letters.
'around' means one lot of letters goes inside another.
'noon' becomes 'n'.
'in'+'huge'='inhuge'
'inhuge' with letters rearranged gives 'unhige'.
'unhige' going around 'n' is 'UNHINGE'.
(Other definitions for unhinge that I've seen before include "Make mentally unstable" , "turn crazy" , "Throw mind into confusion like loose door" , "Madden" , "Drive mad in huge inn" .)