Group of whales given a part in online entertainment (7)
I believe the answer is:
podcast
'online entertainment' is the definition.
(I've seen this in another clue)
'group of whales given a part' is the wordplay.
'group of whales' becomes 'pod' (term for a group of whales).
'given a part' becomes 'cast' (I can't explain this - if you can you should believe this answer much more).
'pod'+'cast'='PODCAST'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for podcast that I've seen before include "Downloadable sound file" , "downloadable files" , "Distribute file(s) via internet to personal computers for playback" , "digital recording" , "Downloadable programme" .)