'anhinga' originates from Portuguese, specifically the word 'anhinga', which was borrowed from Tupi (Tupi–Guarani) 'anhínga' (related to 'Anhangá'), where 'Anhangá' meant 'evil spirit; devil' and was applied to the bird as the 'devil bird.'

'anhinga' was used in Portuguese in Brazil, was adopted into scientific Latin as the genus name 'Anhinga' in the 19th century, and then entered modern English as the common name 'anhinga' for the American snakebird.

Initially, it referred to a supernatural or ominous sense ('devil/forest spirit') in the source language and then to a bird associated with that name; in English it narrowed to the specific long‑necked waterbird(s) of the family Anhingidae.