Outfit of doctor initially entering ship (5)
I believe the answer is:
dress
'outfit' is the definition.
(I've seen this in other clues)
'doctor initially entering ship' is the wordplay.
'doctor' becomes 'dr' (abbreviation).
'initially' suggests taking the first letters.
'ship' becomes 'SS' (prefix in ship names eg SS Great Britain).
The first letter of 'entering' is 'e'.
'dr'+'e'+'ss'='DRESS'
'of' acts as a link.
(Other definitions for dress that I've seen before include "clobber" , "formal attire" , "Something made from fabric" , "One-piece garment" , "Cultivate < tidy" .)