Company doctor's search (4)
I believe the answer is:
comb
'search' is the definition.
(I know that comb is a more specific form of the action search)
'company doctor's' is the wordplay.
'company' becomes 'co' (abbreviation).
'doctor' becomes 'mb' (Bachelor of Medicine, Medicinae Baccalaureus).
'co'+'mb'='COMB'
(Other definitions for comb that I've seen before include "Disentangle" , "Groom; search" , "Toothed object for tidying hair" , "Hair-tidier" , "Search (area) minutely; (cock's) crest" .)