Opahs, also commonly known as moonfish, sunfish (not to be confused with Molidae), kingfish, and redfin ocean pan are large, colorful, deep-bodied pelagic lampriform fishes comprising the small family Lampridae (also spelled Lamprididae).

The family comprises two genera: Lampris (from the Ancient Greek λαμπρός : lamprós, "brilliant" or "clear") and the monotypic Megalampris (known only from fossil remains). The extinct family, Turkmenidae, from the Paleogene of Central Asia, is closely related, though much smaller.

In 2015, Lampris guttatus was discovered to have near-whole-body endothermy in which the entire core of the body is maintained at around 5 °C above the surrounding water. This is unique among fish as most fish are entirely cold blooded or are capable of warming only some parts of their bodies.