Revolutionary laird gets AC, surprisingly (7)
I believe the answer is:
radical
'revolutionary' is the definition.
(radical can mean revolutionary or extreme)
'laird gets ac surprisingly' is the wordplay.
'gets' means one lot of letters go next to another.
'surprisingly' is an anagram indicator (a surprising ordering of the letters).
'laird'+'ac'='lairdac'
'lairdac' is an anagram of 'RADICAL'.
(Other definitions for radical that I've seen before include "Drastic and thorough, as reforms may be" , "Progressive; extreme" , "Total" , "'Revolutionary, extremist (7)'" , "(One) favouring fundamental changes" .)