and it is also the language of Cabo Verde, Guinea, Sao Tome and Principe, Angola and Mozambique. it is also still spoken in the State of GOA in INDIA. and a little in the now Chinese city of MACAO. . Altogether some 270 millions people.
It is portugheza, because it is a noun (meaning the Portuguese language). Portugheză is the adjective, so than the word "limba" has to be there too.
You can use: "limba portugheză" or just "portugheza" .