Disturbed an elevated group (5)
I believe the answer is:
upset
'disturbed' is the definition.
(I know that disturbed can be written as upset)
'an elevated group' is the wordplay.
'an elevated' becomes 'up' (raised up).
'group' becomes 'set' (both can mean a collection).
'up'+'set'='UPSET'
(Other definitions for upset that I've seen before include "Overturn, spill" , "Surprise - distress" , "Capsize" , "Make unhappy; disrupt" , "Disturb or distress" .)