Cycads are a group of very primitive woody plants, often confused with palm trees. They are true living fossils, having had their evolutionary climax in the Mesozoic (about 200 million years ago). In the Triassic and Jurassic periods they were widely distributed, but today the genus Cycas comprises only about 20 species from Polynesia to Madagascar and Japan. C. circinalis is the only representative of the genus on the Indian subcontinent, and more specifically is native to Sri Lanka and southern India.

Like all Cycads, C. circinalis is dioecious and very slow-growing and long-lived. Its seeds are highly neurotoxic, but with proper treatment they produce a flour (sago) used in tortillas, bread and porridge.

C. revoluta and C. circinalis are the two most common species in ornamental use.