名词

1. 攻击；袭击;猛攻
An onslaught on someone or something is a very violent, forceful attack against them.

2. （常指难以应付的）大批，大量
If you refer to an onslaught of something, you mean that there is a large amount of it, often so that it is very difficult to deal with.

1. (military) an offensive against an enemy (using weapons)

e.g. the attack began at dawn

Synonym: attackonsetonrush

2. the rapid and continuous delivery of linguistic communication (spoken or written)

e.g. a barrage of questions
a bombardment of mail complaining about his mistake

Synonym: barragebombardmentoutpouring

3. a sudden and severe onset of trouble