Gengahr are an English indie rock band, formed in 2013 at Stoke Newington School in Hackney, London.

Though originally named RES, they were forced to rename after discovering an artist already called RES on iTunes. Their new name is a play on Gengar, one of the original Pokémon. Their debut album, A Dream Outside, was released on 15 June 2015. In October 2017 it was announced their second album, Where Wildness Grows, would be released on 9 March 2018.

After BBC Radio 1 DJ Huw Stephens played their first single, "Fill My Gums With Blood" on his radio show, the band were invited to perform at the Introducing stage at the 2014 Glastonbury Festival.