The sleek unicornfish was first formally described as Priodon hexacanthus by the Dutch physician, herpetologist and ichthyologist Pieter Bleeker with its type locality given as Ambon Island in the Moluccas, Indonesia.

[4] The sleek unicornfish does not have a protuberance extending from itsforehead, unlike some of its congeners.

Its colors range from a dark brown to yellow, on occasion changing to blue or silver.

[2] The sleek unicornfish is distributed in the Indo-Pacific, from the Hawaiian islands to Africa and India.

[7] As the sleek unicornfish has a wide Indo-Pacific distribution the IUCN has classified its conservation status as Least Concern.