Dismissed soldier is bizarre (5)
I believe the answer is:
outre
'bizarre' is the definition.
('outre' can be a synonym of 'bizarre')
'dismissed soldier' is the wordplay.
I cannot really understand how this works, but
'dismissed' could be 'out' (I've seen this before) and 'out' is found in the answer.
'soldier' could be 're' and 're' is found within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'is' is the link.
Can you help me to learn more?
(Other definitions for outre that I've seen before include "Somewhat unusual" , "Eccentric or unseemly kind of route" , "Peculiar" , "Eccentric, improper" , "Conspicuously unconventional" .)