Myoporum degeneri is a shrub or small tree that can grow up to 7 meters tall, characterized by its deeply fissured bark that is light grey with white blotches. The branches are compressed towards the tips, smooth or obscurely tuberculate, and either glabrous or adorned with scattered glandular hairs, particularly near the leaf bases. The leaves are simple and alternate, with elliptic blades measuring (30–)50–75 x (9–)17–28 mm. They feature an attenuate to aristate apex and a cuneate base that tapers abruptly to the petiole. The upper surfaces of the leaves are dark green and shiny, displaying a glandular pubescent texture. In contrast, the lower surfaces are a lighter green, dull, and very densely glandular-pubescent, giving them a velvety texture. The lamina is thin, with margins that are entire or obscurely serrate. Petioles are 9–15 mm long, and it does not have stipules. The flowers are 5–9 per leaf axil, supported by a pedicel flattened at the base and tetragonous towards the apex, measuring 6–11 mm long. These flowers are bisexual (perfect) and feature a calyx of 5 sepals that are imbricate, ovate, and obscurely keeled, with acute tips and membranous margins towards the base. The sepals are pubescent on the outer surface and margins with both glandular and eglandular hairs, while the inner surface is mostly glabrous except near the apex. The corolla consists of 5 lobes, (3–)4–5 mm long, obtuse, white, sometimes tinged pink, with spots of carmine on the basal part of the lobes and in the tube. The corolla tube is 3–4 mm long, with a glabrous outer surface and pubescent inner surface of the lobes and tube. It has five stamens that are shortly exserted and glabrous. The ovary is superior, conical, 6–7 locular, with one ovule per locule and a glabrous style that persists and becomes more or less circinate after flowering. The fruit is almost dry, conical, and distinctly beaked, measuring 5.5–7.5 x 4.5–5.5 mm. The exocarp is green, turning yellow-brown, with a scarcely developed, slightly succulent mesocarp and a woody endocarp that is conical and tapers into a long beak, 4–6 angled at the base. Seeds are ovoid-oblong, 2.7–3.0 mm long and 0.9–1.0 mm wide, white, tipped brown at the ends. It is found in dry forests between 1100-1475 meters.