Herbs or softly woody shrubs, rarely climbers. Lvs usually opposite, rarely alternate, simple; stipules 0. Fls in cymes, panicles or corymbs, regular, 4-5-merous, usually ☿, sometimes sterile with enlarged petal-like sepals. Calyx 5-merous; tube ± adnate to ovary; sepals imbricate. Petals 4-5, free, contorted or valvate. Stamens twice as many as petals or numerous; anthers basi- or medifixed, 2-locular. Ovary 2-6-locular or incompletely so, 1/2 to fully inferior; styles as many as loculi, free or partly connate; ovules numerous on axile or intrusive parietal placentas, anatropous. Fr. a loculicidal capsule; seeds numerous, small, sometimes winged and reticulate.