Perennials with tall woody stems, broad flat leaf-blades and often leafy inflorescences, rarely small wiry plants of tropical forests or slender herbaceous annuals of tropical marshes. Spikelets borne in panicles, spikes or racemes, 1-many-flowered, occasionally the lowest florets sterile and reduced to glume-like lemmas, upper florets bisexual, becoming male or sterile towards the tip; spikelets disarticulating or persistent with the glumes; lemmas entire, many-nerved, awnless or awned from the apex; lodicules cuneate; stamens 6, rarely more.

Leaf anatomy: vascular bundles circular in section; bundle-sheath double; chlorenchyma diffuse, consisting of arm-cells and often interrupted by fusoid cells; 2-celled micro-hairs slender.

Embryo: scutellum cleft and epiblast present or absent; intemode in the vascular trace absent; first leaf rolled.