Examine a surgical instrument (5)
I believe the answer is:
probe
I believe this clue is a double definition.
'examine' is the first definition.
('probe' can be a synonym of 'examine')
'a surgical instrument' is the second definition.
(probe is a kind of surgical instrument)
(Other definitions for probe that I've seen before include "Inquiry" , "Closely enquire into" , "Investigate closely" , "Intrusive device" , "Poke into" .)