Unethical counterpart to PM against test (6)

I believe the answer is:
amoral
'unethical' is the definition.
(I've seen this before)
'counterpart to pm against test' is the wordplay.
I cannot really see how this works, but
'test' could be 'oral' (oral is a type of examination) and 'oral' is present in the answer.
The remaining letters 'am' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for amoral that I've seen before include "Not knowing right or wrong" , "Lacking principles" , "Ignoring ethical considerations" , "Lacking spiritual values" , "Unconcerned with correctness" .)
