A politician's current abbreviation (3)
I believe the answer is:
amp
'a' is the definition.
(A is the symbol for the amp or ampere)
'politician's current abbreviation' is the wordplay.
I cannot quite understand how this works, but
'politician' could be 'mp' (Member of Parliament) and 'mp' is located in the answer.
A single letter 'a' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for amp that I've seen before include "Sound booster" , "sound is increased by this" , "Unit of electric current - short version" , "In short, unit for measuring electric current" , "It helps you hear" .)