Stimulate understanding for an audience (6)
I believe the answer is:
incite
'stimulate' is the definition.
(I know that incite is a more specific form of the action stimulate)
'understanding for an audience' is the wordplay.
'understanding' becomes 'insight' (insight is a kind of understanding).
'for an audience' shows a homophone (sound like) (as the word might sound to an audience).
'insight' is a homophone of 'INCITE'.
(Other definitions for incite that I've seen before include "Whip up" , "Egg on" , "Foment, urge on" , "Encourage, urge" , "Stir up, urge on to action" .)