Old number one banned from politicians' surgeries (3)
I believe the answer is:
ops
'old number one banned' is the definition.
I can't tell whether this defines the answer.
'from politicians' surgeries' is the wordplay.
'from' becomes 'o' (I've seen this in other clues).
'politicians' surgeries' becomes 'ps' (this could be a standard abbreviation of which I'm unaware).
'o'+'ps'='OPS'
Can you help me to learn more?
(Other definitions for ops that I've seen before include "Military operations" , "medical procedures" , "Military manoeuvres (abbr)" , "facelifts, perhaps" , "Military (or surgical) procedures" .)