If you say that someone is blustering, you mean that they are speaking aggressively but without authority, often because they are angry or offended. 咆哮
verb [vt. 及物动词] 咆哮，气势汹汹地说（但效果不大）；（风暴）呼啸；（雨）倾泻
"That's lunacy," he blustered. “ 真是疯了，” 他吼道。
noun [具体名词] 气势汹汹的话
I wasn't frightened by what he said—it was all bluster. 我没有被他的话吓倒—那不过是在吓唬人。
