Sometimes included in Liliaceae.
Habit and leaf form. Herbs (with erect aerial stems); evergreen, or deciduous. Perennial (annual leaves and flowers). Leaves basal. Plants with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves; rhizomatous, or tuberous. Self supporting, or climbing. Mesophytic, or xerophytic. Leaves alternate (rosette, often withered at flowering); spiral, or distichous; ‘herbaceous’, or leathery, or membranous; sessile; sheathing. Leaf sheaths not tubular; with free margins. Leaves edgewise to the stem, or with ‘normal’ orientation; simple. Leaf blades entire; flat; linear, or lanceolate, or oblong, or ovate (grass-like, may be broad, more or less fleshy above the sheath; apex hooded or obtuse); linear (to filiform); parallel-veined; without cross-venules; sheathing, scarious, sheath fibres more or less persistent. Leaves ligulate, or eligulate; without stipules. Leaf blade margins entire (papillose or ciliate). Leaf anatomy. Hairs absent. Extra-floral nectaries absent. Stem anatomy. Secondary thickening absent.
Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the gynoecium (from septal nectaries).
Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in corymbs, or in panicles (thyrsoid or conical). The terminal inflorescence unit cymose, or racemose (simple or compound). Inflorescences scapiflorous; terminal; inflorescence 1-many flowered; scape leafless; corymb dichotomous; with involucral bracts, or without involucral bracts; pseudanthial, or not pseudanthial. Flowers pedicellate (bracteate, spreading, less than or equal to flower length); bracteate (1 per pedicel, inconspicuous, scarious); ebracteolate; small, or medium-sized; regular; 3 merous; cyclic; pentacyclic, or tetracyclic. Perigone tube absent. Perianth with distinct calyx and corolla (the whorls rather different), or of ‘tepals’; 6; 2 -whorled (3+3); isomerous; free; petaloid; similar in the two whorls, or different in the two whorls; white, or pink, or blue. Calyx (if the outer whorl so interpreted) 3; 1 -whorled; regular. Corolla (if the inner whorl so interpreted) 3; 1 -whorled; regular. Corolla members sometimes fringed, or . Androecial members definite in number. Androecium 6. Androecial members free of the perianth, or adnate (to the perianth); all equal; free of one another; 1 -whorled, or 2 -whorled. Androecium exclusively of fertile stamens, or including staminodes. Staminodes when present, 3. Stamens 6; all more or less similar in shape; isomerous with the perianth, or diplostemonous; hypogynous; alterniperianthial, or oppositiperianthial. Anthers basifixed (almost); versatile; dehiscing via longitudinal slits; introrse; tetrasporangiate. Gynoecium 3 carpelled. The pistil 3 celled. Carpels isomerous with the perianth. Gynoecium syncarpous; synstylovarious, or eu-syncarpous; superior. Ovary plurilocular; 3 locular; sessile. Gynoecium stylate. Styles 1; apical (or nearly so). Stigmas 1; 2–3 - lobed; capitate. Placentation axile. Ovules 4–18 per locule; arillate, or non-arillate; campylotropous (generally), or anatropous.
Fruit and seed features. Fruit non-fleshy (membranous); dehiscent; usually a capsule. Capsules loculicidal. Fruit 3 celled; few per locule. Seeds endospermic. Cotyledons 1. Embryo straight to curved.