Send for a second opinion (5)
I believe the answer is:
refer
'send for a second opinion' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for refer that I've seen before include "Draw attention" , "Hand over for decision" , "Fail (an exam candidate)" , "Send a patient to a specialist" , "Make an allusion, or send on" .)