Opposition to an electrical parameter (10)
I believe the answer is:
resistance
'opposition' is the definition.
(synonyms)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for resistance that I've seen before include "Organised covert opposition to an occupying power" , "defiance" , "French fighting group" , "underground movement" , "Violent opposition" .)