A medium sized tree that can grow up to 15m in height. Crown is bushy and spreading, dull green in colour. Leaves are tiny and sprout from thorny twigs. Flowers are greenish white, in erect panicles. Pods are thick, becoming more coiled as it develops, contains rose-red seeds which are covered in thick white pulp. The tree has many large branches that originate fairly low down on the trunk, resulting in a broad and relatively low crown. The terminal branchlets are thin and numerous, which gives the crown of the tree its characteristic dense but wispy appearance. Leaves are very pretty, with a pair of leaflets on either side of the leaf stalk, but their beauty is tempered by the sharp thorns that lie at their bases. The white flowers of the Madras Thorn are tiny and have numerous, conspicuous stamens. They are borne in heads of 10 to 20 flowers on stalks that reach 30cm or more in length. Fruits are coiled pods which ripen a tinge of rose-red, then split to expose thick white pulp surrounding shiny black seeds that seem to hang out on short, rose-red "strings". The pulp is edible.

The Madras Thorn was once a commonly planted roadside tree in Singapore. During the 1970s, this species suffered from major caterpillar attacks throughout Singapore. The species was phased out from housing estates and roadsides subsequently. Madras Thorn is relatively resistant to fire and resprouts rapidly by basal or aerial shoots. Birds like to feed on the pulp contained in the pods, and this is how the seeds are spread. A native of Tropical America, it was introduced to this region by the Portugese and the Spanish. The common name of the species indicates people do adopt plants as their own. This species has uses as a fodder plant, the wood can be used in rough construction or as firewood, its bark yields gums and tannins and the pulp can be eaten and made into a juice. Its name Pithecellobium cames from the Greek word 'pithekos', meaning an ape or a monkey and 'lobos', a pod or a lobe. In Latin, 'dulce' means sweet.