A doctor during excursion produces drum (7)
I believe the answer is:
tambour
'drum' is the definition.
(tambour is a kind of drum)
'a doctor during excursion' is the wordplay.
'doctor' becomes 'mb' (Bachelor of Medicine, Medicinae Baccalaureus).
'during' is an insertion indicator.
'excursion' becomes 'tour' (I've seen this before).
'a'+'mb'='amb'
'amb' inserted within 'tour' is 'TAMBOUR'.
'produces' is the link.
(Other definitions for tambour that I've seen before include "circle for 13 [NEEDLEWORK]" , "Beat this" , "feature of some courts" , "Circular frame to hold fabric tight for embroidery" , "Drum or embroidery frame" .)