Rockcod is a term applied to several unrelated fishes, which all look roughly cod-like and live among rocky habitat. Most are of some importance in fisheries.
In the codling family (Moridae): Lotella rhacina, the Rock Cod proper
In the cod icefish family (Nototheniidae) Eleginops Notothenia Paranotothenia Trematomus
In the grouper family (Serranidae): Epinephelus Cephalopholis
"Rockcods" is also an alternate name for the thornyhead family (Sebastidae).