The grey-breasted sabrewing (Campylopterus largipennis) is a species of hummingbird in the "emeralds", tribe Trochilini of subfamily Trochilinae.

[6] The bird was also illustrated in a hand-colored plate engraved by François-Nicolas Martinet in the Planches Enluminées D'Histoire Naturelle which was produced under the supervision of Edme-Louis Daubenton to accompany Buffon's text.

[7] Neither the plate caption nor Buffon's description included a scientific name but in 1783 the Dutch naturalist Pieter Boddaert coined the binomial name Trochilus largipennis in his catalogue of the Planches Enluminées.

The Clements taxonomy and BirdLife International's Handbook of the Birds of the World (HBW) recognize only two by including aequatorialis within obscurus.

[15] The three subspecies of grey-breasted sabrewing recognized by the IOC are distributed thus:[3][15] The species inhabits humid primary and secondary forest, clearings within them, and plantations.

It places it like a saddle on a horizontal branch or attaches it to hanging twigs, typically near waterfalls or running streams and within about 1 m (3 ft) of the ground.

The grey-breasted sabrewing makes "repeated short chik or trzik" calls and "occasionally a faster stuttering series."