Mission to put hospital in centre (5)
I believe the answer is:
chore
'mission' is the definition.
(thesaurus)
'hospital in centre' is the wordplay.
'hospital' becomes 'h' (abbreviation for hospital on maps).
'in' means one lot of letters goes inside another.
'centre' becomes 'core' (core can mean something's centre).
'h' placed into 'core' is 'CHORE'.
'to put' is the link.
(Other definitions for chore that I've seen before include "Unpleasant task" , "Household job" , "A household or routine task" , "easy option? Not so!" , "Boring job" .)