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Onychoprion, the "brown-backed terns", is a genus of seabirds in the family Laridae. 
The genus name is from Ancient Greek onux, "claw" or "nail", and prion, "saw".

1/ Bridled tern (Nhàn lưng đen, Onychoprion anaethetus)
The specific anaethetus means "senseless, stupid".

2/ Sooty tern (Nhàn nâu, Onychoprion fuscatus), coloquially wideawake tern or just wideawake
The specific fuscatus is Latin for "dark".

Sooty tern (Nhàn nâu, Onychoprion fuscatus), coloquially wideawake tern or just wideawake

The sooty tern (Onychoprion fuscatus) is a tern in the family Laridae.

Charadriiformes, Charadriidae, Charadrius: Late Latin word for a yellowish bird mentioned in the fourth-century Vulgate; from Ancient Greek kharadrios a bird found in ravines and river valleys (kharadra, "ravine").

Laridae:from Ancient Greek laros or Latin larus, which appears to have referred to a gull or other large seabird.

The genus name Onychoprion is from Ancient Greek onux, "claw" or "nail", and prion, "saw".

The specific fuscatus is Latin for "dark".