Of uncertain origin. Attempts have been made to derive it from various Germanic and Slavic roots. It was certainly in use in Poland in the 19th century, and is found in Polish folk tales as the name of a princess. The derivation may well be from the ethnic term Wend (see Wendell). The name was introduced to the English-speaking world by Ouida (Marie Louise de la Ramée), who used it for the heroine of her novel Wanda (1883).
English (especially Yorkshire) and Scottish: occupational name for a fuller, Middle English walkere, Old English wealcere, an agent derivative of wealcan ‘to walk, tread’. This was the regular term for the occupation during the Middle Ages in western and northern England. Compare Fuller and Tucker. As a Scottish surname it has also been used as a translation of Gaelic Mac an Fhucadair ‘son of the fuller’.