Blue wildebeest is placed in the family Bovidae, ruminant animals with cloven hooves. The generic name "Connochaetes" derives from the Greek words κόννος, kónnos, "beard", and χαίτη, khaítē, "flowing hair", "mane". The specific name "taurinus" originates from the Greek word "tauros", which means a bull or bullock. The common name "blue wildebeest" refers to the conspicuous, silvery-blue sheen of the coat, while the alternative name "gnu" originates from the name for these animals used by the Khokloi people, a native pastoralist people of southwestern Africa. Though the blue and black wildebeest are currently classified in the same genus, the latter was previously
Black wildebeest to hybridise with its taxonomically close relative, the blue wildebeest. Male black wildebeest have been reported to mate with female blue wildebeest and vice versa. The differences in social behaviour and habitats have historically prevented interspecific hybridisation between the species, but hybridisation may occur when they are both confined within the same area. The resulting offspring is usually fertile. A study of these hybrid animals at Spioenkop Dam Nature Reserve in South Africa revealed that many had disadvantageous abnormalities relating to their teeth, horns, and the wormian bones in the skull. Another study reported an increase in the size of