Long-billed plover (Choi choi lớn, Thinornis placidus)
Formerly belonging to the genus Charadrius

The long-billed plover (Thinornis placidus) is a species of wading bird in the family Charadriidae.
The bird can be found in Bangladesh, Bhutan, Brunei, Cambodia, China, Hong Kong, India, Indonesia, Japan, Laos, Malaysia, Mongolia, Myanmar, Nepal, North Korea, Russia, South Korea, Sri Lanka, Taiwan, Thailand, and Vietnam.

Charadrius, Charadriidae or Charadriiformes comes from the Ancient Greek kharadrios, meaning a bird found in river valleys or ravines ((kharadra) being ravine), and was later adopted into Late Latin. The Latin word Thinornis described a yellowish bird mentioned in the Vulgate Bible.

The genus name Thinornis is derived from Ancient Greek: "this" or "thinos" meaning "beach" or "sand," combined with "ornis" meaning "bird". Therefore, Thinornis literally translates to "beach bird" or "sand bird". 

Placidus is a Latin word meaning "gentle," "calm," "mild," "peaceful," or "placid".