BROMUS, in botany, a genus of the triandria digynia class. The calix is double-valved; the spica is oblong and cylindrical; the awn is below the apex. There are 17 species, eight of which are natives of Britain, viz. the fecalinus or field brome-grass, the arvensis or corn brome-grass, the ciliatus or wall brome-grass, the sterilis or barren brome-grass, the giganteus or tall brome-grass, the ramosus or wood brome-grass, and the pinnatus or spiked brome-grass.