The Spanish and Portuguese version of 'John Doe' or 'John Q. Public'.

From the words fulano*, most often translated as 'so-and-so' (or sometimes simply as 'person'), de, meaning 'of', and tal, meaning 'such'. Pronounced Foo-la-no day tal. A female is 'fulana de tal'.

It is often used as a joke name, in which case it is capitalized as Fulano de Tal. It is properly written as a surname (Sr. Fulano de Tal, Prof. Fulano de Tal).

Another portuguese phrase with the same meaning is Ciclano de tal.

* The word fulano also appears in the phrase fulano, zutano, y mengano, which translates (although not literally) as 'Tom, Dick, and Harry'. To the best of my knowledge, Fulano is not an actual surname.