Scaevola chamissoniana are typically shrubs, sometimes resembling small trees, with a height ranging from 1.5 to 2.5 meters. The leaves are simple and alternate, with blades broadly oblanceolate, measuring 9–14 cm in length and 2–4 cm in width. The apex of the leaves is acute-acuminate, while the base is acuminate, with surfaces that are either glabrous or sparsely pubescent. The margins of the leaves are usually toothed on the distal half to two-thirds. The petioles are short, 1 to 3 cm long, and stipules are absent. The flowers are (3–)7–15 or more in number, arranged in open cymes that span 100–150 mm, making them as long as or longer than the leaves themselves. The peduncles of these cymes extend 40–110 mm, and each is subtended by paired, narrowly oblanceolate bracteoles that are 3–10 mm long. The flowers are noted for their strong fragrance and distinct irregularity, featuring a calyx that is minute and 5-parted and a corolla that is funnelform-unilabiate, 5-parted with the tube split adaxially. The corolla is white, often adorned with purple lines on its inner surface, and glabrous, measuring (17–)24–30 mm long for the tube, with lobes that are (8–)12–15(–18) mm long, spreading, and winged. The stamens, which are about as long as the corolla tube, are distinct, with introrse, dithecal anthers that open by longitudinal slits. Pollen is shed from the coherent anthers and collected by the indusium on the outgrowing style. The fruit is drupaceous, 2-celled, dark purplish black, ovoid, measuring 12–14 mm long and 6–8 mm in diameter, and it is either glabrous or sparsely pubescent. The seeds are numerous and contain oily endosperm. It is found in wet forests and open areas, predominantly at an elevation of approximately 350 meters.