The sooty tern (Onychoprion fuscatus) (formerly Sterna fuscata), is a seabird of the tern family (Sternidae). It is a bird of the tropical oceans, breeding on islands throughout the equatorial zone. Colloquially, it is known as the wideawake tern or just wideawake. This refers to the incessant calls produced by a colony of these birds, as does the Hawaiian name ʻewa ʻewa which roughly means "cacophony".