Wedge-tailed green pigeon or Kokla green pigeon 
(Cu xanh sáo, Treron sphenurus)

The wedge-tailed green pigeon or Kokla green pigeon (Treron sphenurus) is a species of bird in the family Columbidae.

The bird is found in the Indian Subcontinent and Southeast Asia. It ranges across Bangladesh, Bhutan, Cambodia, India, Indonesia, Laos, Malaysia, Myanmar, Nepal, Thailand, Tibet and Vietnam.

Columbidae, Columba: Latin columba (“dove, pigeon”). Ancient Greek κόλυμβος (kólumbos, “a diver”), from κολυμβάω (kolumbáō, “dive, plunge headlong, swim”).
Pigeon is a French word that derives from the Latin pīpiō, for a "peeping" chick;
Dove is an ultimately Germanic word that refers to the bird's diving flight.
The genus name Treron is from the Ancient Greek trērōn meaning "pigeon" or "dove".