Onslaught (6)
'onslaught' is the definition.
(synonyms)
This is all the clue.
(Other definitions for attack that I've seen before include "Pitch into" , "Assault or criticise violently" , "mount an offensive" , "Offensive action" , "Fiercely criticise" .)
'onslaught' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for assault that I've seen before include "raid" , "Launch an attack on" , "set about" , "Sort of course" , "Strike" .)