What's entertained us -- dame cavorting (6)
I believe the answer is:
amused
'what's entertained' is the definition.
(amusing is a kind of entertaining)
'us dame cavorting' is the wordplay.
'cavorting' indicates anagramming the letters.
'us'+'dame'='usdame'
'usdame' with letters rearranged gives 'AMUSED'.
(Other definitions for amused that I've seen before include "happily occupied" , "Provoked mirth in" , "Victoria reputedly wasn't" , "Pleasantly occupied" , "Medusa (anag)" .)