I ran away from Australians in Rush (7)
I believe the answer is:
assault
'rush' is the definition.
(thesaurus)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for assault that I've seen before include "Violent attack in action or words" , "Onslaught" , "Mount an attack" , "raid" , "Attack associated with" .)