Dark purple-blue along the back, shading to paler iridescent blue on the upper side and mirror-like silver below. The fins are dark grey. Hoki have an easily recognisable long, thin body with a tapering tail fringed by dorsal and anal fins. The eyes and jaws are large. The teeth are small and sharp.

Hoki belong to the Merlucciidae family (hakes). They are one of New Zealand's most important commercial deepwater species. Hoki are caught by trawling all around New Zealand and are most common in Cook Strait and off the west coast of South Island during the winter spawning season. At other times of the year they are fished on the Chatham Rise and in the south on the Campbell Plateau.

They generally live beyond the shelf edge and are most abundant between 300 to 600 metres. Adult fish have been found at depths from 50 metres down to 900 metres. The juveniles often live in shallower water, where growth is rapid. Adults are between five and 20 years old.

Hoki are also found off the coast of South Australia and a related species, Macruronus magellenicus, is found off South America.