Note: Australia is generally considered to be a continental landmass, rather than an island. If however one does count Australia among the islands it, not Greenland, would be the largest in the world (unless one also considered Antarctica an island).
... (1491-1557), discovered the St. Lawrence River and sailed up it to Montreal; failed in an attempt to set up a colony
Thomas Cavendish, (died 1592), English sailor and ...