Mayda (variously known as Maida, Mayd, Mayde, Brazir, Mam, Asmaida, Asmayda, Bentusle, Las Maidas Bolunda and Vlaanderen[1][2]) is a non-existent island in the North Atlantic that has been shown on several published maps at various points in history.

It was crescent-shaped and sited southwest of the island of Brasil, on the same latitude of southern Brittany.

[3] It appeared as Asmaidas on a map of the New World accompanying Waldseemüller's 1513 edition of Ptolemy's Geography.

[4] Ortelius (in Theatrum Orbis Terrarum) placed a crescent-shaped island in the traditional location of Mayda with the name "Vlaenderen" ("Flanders").

[5] Submerged land of the appropriate shape has been found in the area of early maps (46°23′N 37°20′W / 46.383°N 37.333°W / 46.383; -37.333) at a depth of 20 fathoms (120 ft; 37 m) which suggested to one author that Mayda may have existed.