The Pacific kingfisher was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae.

[1] Gmelin based his description on the "sacred kingfisher" that had been described and illustrated in 1782 by the English ornithologist John Latham in his multi-volume A General Synopsis of Birds.

Latham had access to a specimen in the Leverian Museum in London that had been collected during James Cook's third voyage to the Pacific Ocean from 1776 to 1780.

[6][7] The word Todiramphus combines the genus name Todus with the Ancient Greek rhamphos meaning "bill".

It is usually seen further inland than the collared kingfisher, where it was previously considered conspecific, ranging into forest or into mountain areas.

When it spots something it glides down to catch it and then flies back to the perch where larger items are pounded against the branch to subdue them.