White-bellied green pigeon 
(Cu xanh Bụng Trắng, Treron sieboldii)

The white-bellied green pigeon (Treron sieboldii) is a species of bird in the family Columbidae.
This bird species is is found in China, Japan, South Korea, Laos, Russia, Taiwan, Thailand, India 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".

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