[Tupi boi-una, serpens obscurus (Martins). Carried by the Portuguese from Brazil to Ceylon.]
a. A large water-snake of Brazil of dark color (? Boa aquatica). b. A harmless snake of Ceylon.
1774. Goldsm., Nat. Hist. (1862), II. III. iii. 429. The Boyuna of Ceylon is equally a favourite among the natives.