Cyanea elliptica is a branched shrub reaching 1–4 meters in height. The leaves are simple and alternate. Blades are elliptic to oblong, measuring 8–18 cm long and 2.8–7 cm wide. The apex is obtuse to acute, and the base is rounded to obtuse. Upper surfaces are green and glabrous, while lower surfaces are pale green and either glabrous or pubescent along the midrib. Margins are callose–crenulate to callose–serrulate. Petioles are 2.5–6.5 cm long. Stipules are absent. The flowers occur in axillary inflorescences of 6–14 flowers. The rachis is condensed or obsolete, with peduncles 10–50 mm long and pedicels 5–20 mm long. The hypanthium is obovoid, 3–4 mm long, and 2–3 mm wide. Flowers are bisexual (perfect). The calyx has 5 dentiform lobes, 0.5–1 mm long, distinct or rarely connate, with pubescent margins. The apex is acute to acuminate, and the tube is adnate to the ovary. The corolla is zygomorphic (bilaterally symmetric), greenish-white or white-tinged purplish, 15–22 mm long, and 1.5–3 mm wide, with a glabrous surface. The tube is suberect, and the lobes are spreading. Stamens are 5, alternate with corolla lobes, and connate, forming a glabrous staminal column. Anthers are glabrous, with the lower two bearing apical tufts of white hairs. Anthers are dithecal, opening by longitudinal slits, and may be coherent but separate after anthesis or form a tube into which pollen is shed. The ovary is inferior and 2-celled, with axile placentation. The stigma is 2-lobed, spreading apart to become receptive after the style pushes out pollen. The fruits are purple, globose berries 6–9 mm in diameter. The seeds are numerous, small, brown to black, smooth, shiny, and measure 0.4–0.5(–2) mm long. The seeds contain a straight, short to spatulate, dicotyledonous embryo embedded in oily endosperm. It is found in mesic valleys and forests between 475–915 meters.