Plants summer or winter annuals or perennials; cespitose, sometimes shortly rhizomatous. Culms to 135(150) cm, erect, geniculate, or decumbent; nodes glabrous or pubescent. Sheaths open, pubescent or glabrous; auricles present or absent; ligules hyaline, truncate, erose; blades flat to more or less involute, more or less pubescent on both sides. Inflorescences usually spikelike racemes, sometimes spikes, all customarily called spikes, with 3 spikelets at each node, central spikelets usually sessile, sometimes pedicellate, pedicels to 2 mm, lateral spikelets usually pedicellate, pedicels curved or straight, sometimes all 3 spikelets sessile in cultivated plants; disarticulation usually in the rachises, the spikelets falling in triplets, cultivated forms generally not disarticulating. Spikelets with 1 floret; glumes awnlike, usually exceeding the floret. Lateral spikelets usually sterile or staminate, often bisexual in cultivated forms; florets pedicellate, usually reduced; lemmas awned or unawned. Central spikelets bisexual; florets sessile; rachillas prolonged beyond the floret; lemmas ovate, glabrous to pubescent, 5-veined, usually awned, rarely unawned; paleas almost equal to the lemmas, narrowly ovate, keeled; lodicules 2, broadly lanceolate, margins ciliate; anthers 3, usually yellowish. Caryopses usually tightly enclosed in the lemma and palea at maturity. 2n = 14, 28, 42. Name from the old Latin name for barley.