Laws are crucial tools to protect wetlands. How these laws are written has important implications for conservation. We assessed all wetland terms and definitions in Brazilian legislation to identify whether legislation uses any generic terms to represent several or all types of wetlands and to determine if definitions with clear descriptors exist that can easily be used to identify wetland systems. A total of 116 local wetland-related terms and 21 wetland definitions were found in Brazilian legislation. A direct Portuguese translation of the term ‘wetlands’ was found only once in the New Forest Code. The insertion of the term ‘wetlands’ in the New Forest Code has important practical implications for the conservation, since all different Brazilian wetland types would be represented by the generic term ‘wetlands’. The existence of a definition of the term ‘wetlands’ associated with attributes of water and biota in Federal legislation will help environmental technicians to identify wetland systems and to recognize different wetland types. The insertion of this definition in the New Forest Code would make it clear that the drainage of any wetland type – large or small – is prohibited, and those who do so would be breaking Brazilian environmental law.