Swiss hero absorbing a tirade over a lively dance (10)
I believe the answer is:
tarantella
'lively dance' is the definition.
(I've seen this before)
'swiss hero absorbing a tirade over a' is the wordplay.
'swiss hero' becomes 'Tell' (folk hero William Tell).
'absorbing' means one lot of letters goes inside another.
'tirade' becomes 'rant' (both can mean an angry outburst).
'over' says to put letters next to each other (in a down clue, some letters go over others).
'a'+'rant'='arant'
'tell' placed around 'arant' is 'tarantell'.
'tarantell'+'a'='TARANTELLA'
(Other definitions for tarantella that I've seen before include "Whirling dance" , "dance music" , "Lively Neapolitan dance" , "merry dance" , "Lively Italian dance" .)