大维齐尔（土耳其语：Sadr-ı Azam、Serdar-ı Ekrem，鄂图曼土耳其语：صدر اعظم）源自阿拉伯语「维齐尔」（وزير），是苏丹以下最高级的大臣，相当于宰相的职务，拥有绝对的代理权，原则上只有苏丹才能解除此权。大维齐尔持有帝国印章，能召集所有维齐尔参与国家事务，会议举行的地方叫「库巴尔提」（圆穹下），位于托卡比皇宫。他的政府机关在最高朴特。大维齐尔也是巴基斯坦总理的乌尔都语尊称。

在鄂图曼帝国初期，「维齐尔」只用于尊称。首位被冠以「大维齐尔」称号的是**尔勒·卡拉·哈利勒·海雷丁帕夏。创立「大维齐尔」称号的目的是要区别持有苏丹印章的维齐尔。综观鄂图曼帝国的历史，大维齐尔也会使用「最高维齐尔」（صدر عالی）、「绝对代理人」（وكیل مطلق）、「国家持有者」（صاحب دولت）及「维齐尔人」（ذات آصفی）的称号。

In the Ottoman Empire, the Grand Vizier was the prime minister of the Ottoman sultan, with absolute power of attorney and, in principle, dismissible only by the sultan himself. He held the imperial seal and could convene all other viziers to attend to affairs of the state; the viziers in conference were called "Kubbealtı viziers" in reference to their meeting place, the Kubbealtı ('under the dome') in Topkapı Palace. His offices were located at the Sublime Porte.