Dodonaea viscosa has simple, alternate leaves with blades that are elliptic to oblanceolate, spatulate, or lanceolate to oblong-lanceolate. These leaves range in size from 2 to 15 cm in length and 0.5 to 6 cm in width. The leaf apex varies from rounded to obtuse or acuminate, typically bluntly mucronate with a purple-tinged mucro, and occasionally emarginate. The leaf base is attenuate to cuneate. The leaf surfaces are sparsely to occasionally densely short-hispidulous on and near veins and margins, sometimes glabrous. The blades are membranous to chartaceous, sometimes subcoriaceous, glandular punctate, and usually irregularly viscid-varnished. The margins are entire, sometimes slightly revolute or undulate. The petioles are short, 0.1 to 1.1 cm long, and slightly winged. Stipules are absent. The flowers form in paniculate inflorescences, typically 1 to 5 cm long, with pedicels usually 3 to 10 mm long, short-hispidulous, and usually viscid. The flowers are unisexual, with the plants being dioecious, sometimes andromonoecious or functionally monoecious, and occasionally bisexual. The calyx is deeply 3 to 5-lobed, with 4 to 6 sepals that are oblong-oblanceolate to linear-lanceolate, 1.5 to 2.2 mm long, short hispidulous toward the margins to nearly glabrous, and persistent. There are no petals. Staminate flowers have 7 to 10 stamens, with anthers 2 to 3 mm long and a vestigial ovary. The superior ovary in pistillate flowers is usually densely short-hispidulous, with 2 to 4 cells and styles 2 to 4, 2 to 9 mm long. The fruit is a capsule, straw-colored to dark reddish-purple, exceedingly variable in shape, ranging from turgid to inflated, bladdery, or compressed. The body of the capsule is 0.5 to 1.5 cm long, with 2 to 4 wings, each being 1 to 6 mm wide. The seeds are compressed-ovoid, approximately 2 mm long. It is found in various habitats such as coastal dunes, lava fields, and dry, mesic, and wet forests between 0-2300 meters.