In front of us is Nurse Bell (7)
I believe the answer is:
angelus
'bell' is the definition.
(angelus is a kind of bell)
'in front of us is nurse' is the wordplay.
'in front of' means one lot of letters go next to another (some letters go in front of others).
'is nurse' becomes 'angel' (angel can informally mean a nurse).
'us' after 'angel' is 'ANGELUS'.
(Other definitions for angelus that I've seen before include "Church bell" , "Thrice daily prayer of Roman Catholics" , "(Bell calling Catholics to) prayer" , "Midday prayer" , "Prayer at noon and 6pm" .)