Stems forming loose mats; branches lax, tips barely, if at all ascending. Leaves loosely appressed; blade linear to subulate, 2–3 × 0.5–0.8 mm, (ciliolate), apex acute. Pedicels (deep red), 0.7–1.5 cm, 3+ times longer than leaves at anthesis. Flowers erect; sepals ovate, ca. 2 mm; corolla white, ca. 4 × 3 mm, lobes distinct for ca. 1/2 their lengths, tips not recurved; stamens to 1.5 mm. Capsules 2–3.5 mm diam. 2n = 32, 48.

Subshrubs, shrubs, vines, or trees, usually multicellular-hairy (margins of leaves usually glandular-hairy), or sometimes absent (Andromeda); bark smooth or furrowed, not flaky. Stems erect, arching, spreading, creeping, or procumbent. Leaves deciduous or persistent, alternate, sometimes pseudoverticillate (Pieris); petiole usually present, sometimes absent (some species of Vaccinium); blade plane, abaxial groove absent. Inflorescences usually axillary, sometimes terminal, usually panicles or racemes, sometimes corymbs or fascicles, sometimes solitary flowers, (borne on leafy twigs, except Zenobia on leafless twigs); perulae absent; bracts much shorter than sepals (sometimes absent). Flowers pendulous; perianth and androecium hypogynous or epigynous (Gaylussacia, Vaccinium); sepals (4–)5[–8]; petals 4–5(–6), connate (rarely distinct or nearly so in some species of Vaccinium), corolla deciduous, campanulate, cylindric, or urceolate, lobes usually much shorter (sometimes longer) than tube; intrastaminal nectary disc absent or present; stamens 8–10[–16]; anthers dehiscent by terminal pores or short slits; ovary 5- or 10-locular; placentation axile; style straight. Fruits capsular, dehiscence loculicidal, or baccate or drupaceous, indehiscent. Seeds 2–300, distinct, ovoid or obovoid to ellipsoid, lanceoloid, or conic, to angular or wedge- or crescent-shaped, usually not winged, sometimes slightly winged or tailed.