Protective garment a professional nurse first needed (5)
I believe the answer is:
apron
'protective garment' is the definition.
(apron is a kind of protective garment)
'a professional nurse first needed' is the wordplay.
'professional' becomes 'pro' (abbreviation).
'nurse first' becomes 'n' (1st letter of 'nurse').
'needed' is a charade indicator (letters next to each other).
'a'+'pro'+'n'='APRON'
(Other definitions for apron that I've seen before include "Garment for protection" , "Kitchen garment or part of airfield" , "Protective garment - part of stage" , "Protective garment worn at front" , "Area for aircraft not in use" .)