Older lady is one acting to acquire comic (7)
I believe the answer is:
dowager
'older lady' is the definition.
(dowager can informally mean an elderly woman)
'one acting to acquire comic' is the wordplay.
'one acting' becomes 'doer' (I've seen this in another clue).
'to acquire' indicates putting letters inside.
'comic' becomes 'wag' (wag can mean a comical person).
'doer' placed around 'wag' is 'DOWAGER'.
'is' acts as a link.
(Other definitions for dowager that I've seen before include "Important widow" , "woman of status" , "Dignified (or wealthy) elderly woman" , "Widow, imposing elderly woman" , "woman of property?" .)