Doctor slips hurrying out of hospital unexpectedly (12)
I believe the answer is:
surprisingly
'unexpectedly' is the definition.
(I've seen this before)
'doctor slips hurrying out of hospital' is the wordplay.
'doctor' is an anagram indicator.
'out of' is a deletion indicator.
'hospital' becomes 'h' (abbreviation for hospital on maps).
'slips'+'hurrying'='slipshurrying'
'slipshurrying' with 'h' removed is 'slipsurrying'.
'slipsurrying' anagrammed gives 'SURPRISINGLY'.
(Other definitions for surprisingly that I've seen before include "Unexpectedly" , "Amazingly" .)