Active sort about to shake old woman (7)
I believe the answer is:
dowager
'old woman' is the definition.
(thesaurus)
'active sort about to shake' is the wordplay.
'active sort' becomes 'doer' (I've seen this in another clue).
'about' means one lot of letters goes inside another.
'to shake' becomes 'wag' (synonyms).
'doer' going around 'wag' is 'DOWAGER'.
(Other definitions for dowager that I've seen before include "Important widow" , "old lady" , "Titled widow" , "Widow inheriting husband's title or property" , "woman of status" .)