全部付清, 按时付款, (在勒索下)出钱
【经】 付清, 缴清(股款等)
在线英汉词典

pay up的短语、例句：

pay up pay in full money that is owed for sth 付清全部欠款
I´ll take you to court unless you pay up immediately. 除非马上还清欠款, 否则我和你打官司.