PM, a teetotaler and a general (6)
I believe the answer is:
attlee
'pm' is the definition.
(prime minister Clement Attlee)
'a teetotaler and a general' is the wordplay.
'a teetotaler' becomes 'att' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'and' means one lot of letters go next to another.
'a general' becomes 'Lee' (Robert E. Lee - US revolutionary commander).
'att'+'lee'='ATTLEE'
Can you help me to learn more?
(Other definitions for attlee that I've seen before include "Prime minister nineteen forty five to fifty one" , "Clement --, former PM" , "Labour PM" , "Granny Smiths perhaps" , "Clement -, PM nineteen forty five - fifty one" .)