角马（Connochaetes），也叫牛羚，是一种生活在非洲草原上的大型羚羊。在生物分类学上，它指的是属于牛科的狷羚亚科的角马属。

角马属有两种，白尾角马和斑纹角马。

角马的头粗大而且肩宽，很像水牛；后部纤细，比较像马；颈部有黑色鬣毛。全身有长长的毛，光滑并有短的斑纹。全身从蓝灰到暗褐色，有黑色的脸、尾巴、胡须和斑纹，颜色也因亚种、性别和季节的不同而有所变化。角马有飘垂的鬃须，长而成簇的尾，雌雄两性都有弯角，雄性的又宽又厚，非常光滑，一般雄性角长55~80cm，雌性角长45~63cm，角马由此得名。雄性角马重200~274kg，高125~145cm，雌性角马重168~233kg，高115~142cm。

The wildebeests, also called gnus or wildebai, are a genus of antelopes, Connochaetes. They belong to the family Bovidae, which includes antelopes, cattle, goats, sheep and other even-toed horned ungulates. Connochaetes includes two species, both native to Africa: the black wildebeest, or white-tailed gnu (C. gnou); and the blue wildebeest, or brindled gnu (C. taurinus). Fossil records suggest these two species diverged about one million years ago, resulting in a northern and a southern species. The blue wildebeest remained in its original range and changed very little from the ancestral species, while the black wildebeest changed more in order to adapt to its open grassland habitat in the south. The most obvious way of telling the two species apart are the differences in their colouring and in the way their horns are oriented.