Exhibit courage finally in conflict (4)
I believe the answer is:
wear
'exhibit' is the definition.
'courage finally in conflict' is the wordplay.
'finally' says to take the final letters.
'in' is an insertion indicator.
'conflict' becomes 'war' (war is a kind of conflict).
The final letter of 'courage' is 'e'.
'e' inserted into 'war' is 'WEAR'.
(Other definitions for wear that I've seen before include "Tire; dress in" , "Dress in - impair - abrade - change course - river" , "Northern runner" , "North-east flower" , "Durham's river - erosion" .)