Bacalhau is the Portuguese word for cod and—in a culinary context—dried and salted cod. Fresh (unsalted) cod is referred to as bacalhau fresco.

Fishing is a major economic activity in Portugal. The country has a long tradition in the sector, and is among the countries in the world with the highest fish consumption per capita. Roman ruins of fish processing facilities were found across the Portuguese coast. Fish has been an important staple for the entire Portuguese population, at least since the Portuguese Age of Discovery.