Much of East Anglia redeveloped — effect of numbers? (9)
I believe the answer is:
analgesia
'effect of numbers?' is the definition.
(things which numb pain cause analgesia)
'much of east anglia redeveloped' is the wordplay.
'much of' means to remove the last letter.
'redeveloped' indicates anagramming the letters.
'east' with its last letter removed is 'eas'.
'eas'+'anglia'='easanglia'
'easanglia' anagrammed gives 'ANALGESIA'.
(Other definitions for analgesia that I've seen before include "painless" , "No hard feelings" , "Absence of pain" , "As a linage (anag) - insensibility to pain" , "Inability to feel pain" .)