State lucky to be evacuated altogether (7)
I believe the answer is:
utterly
'altogether' is the definition.
('utterly' can be a synonym of 'altogether')
'state lucky to be evacuated' is the wordplay.
'state' becomes 'utter' (I've seen this before**).
'to be evacuated' means to remove the middle letters.
'lucky' with its middle taken out is 'ly'.
'utter'+'ly'='UTTERLY'
(Other definitions for utterly that I've seen before include "Absolutely and completely" , "Completly and without qualification" , "Completely and totally" , "'All is changed, changed . . .' (Yeats)" , "Downright" .)