Tiny and rather unobtrusive bird with brownish upperparts and luminous lemon-yellow underparts. Superficially similar to female and juvenile Olive-backed Sunbirds, but note gerygone’s short, uncurved bill. Forages in parks, forests, and plantations, where it often joins mixed flocks moving through the middle and upper layers. Song is variable throughout its range but invariably includes buzzy notes with obvious rises and falls in pitch.