Writer organising attic's high area (6,8)
I believe the answer is:
agatha christie
'writer' is the definition.
(I've seen this before)
'organising attic's high area' is the wordplay.
'organising' indicates an anagram.
'attics'+'high'+'area'='atticshigharea'
'atticshigharea' anagrammed gives 'AGATHA CHRISTIE'.
(Other definitions for agatha christie that I've seen before include "One who wrote" , "Detective story writer" , "author" , "[THE QUEEN OF CRIME] - with 16d" .)