Calling hospital before being unwell (7)
I believe the answer is:
hailing
'calling' is the definition.
(hailing is a kind of calling)
'hospital before being unwell' is the wordplay.
'hospital' becomes 'H' (abbreviation for hospital on maps).
'before' is a charade indicator (letters next to each other).
'being unwell' becomes 'ailing' ('ailing' can be a synonym of 'unwell').
'h'+'ailing'='HAILING'
(Other definitions for hailing that I've seen before include "Waving to (a taxi)" , "Greeting" , "Raining ice" .)