Ruvettus ruvettus, commonly known as the oilfish, is a species of fish found in deep ocean waters. It belongs to the family Gempylidae and is known for its elongated body and dark blue to gray coloration. Oilfish can grow up to 2 meters in length and are characterized by their high oil content, which gives them a unique texture and flavor. This fish is primarily found in tropical and temperate regions of the Atlantic Ocean, Indian Ocean, and Pacific Ocean. Due to its high fat content, particularly in the form of wax esters, oilfish is often avoided by some consumers, as it can cause digestive issues if not prepared properly.