(male) Probably the most successful of all the Old French names of Germanic origin that were introduced to England by the Normans. It is derived from Germanic wil ‘will, desire’ + helm ‘helmet, protection’. The fact that it was borne by the Conqueror himself does not seem to have inhibited its favour with the ‘conquered’ population: in the first century after the Conquest it was the commonest male name of all, and not only among the Normans. In the later Middle Ages it was overtaken by John, but continued to run second to that name until the 20th century, when the picture became more fragmented.
Short forms: Will, Bill.
Pet forms: Willy, Willie, Billy.
Cognates: Irish: Uilliam. Scottish Gaelic: Uilleam. Welsh: Gwilym. German: Wilhelm. Dutch: Willem. Scandinavian: Vilhelm. French: Guillaume. Spanish: Guilermo. Catalan: Guillem. Portuguese: Guilherme. Italian: Guglielmo. Czech: Vilém. Slovenian: Viljem. Hungarian: Vilmos. Lithuanian: Vilhelmas. Latvian: Vilhelms.
Scottish and English (of Norman origin): habitational name for someone from Rots near Caen in Normandy, probably named with the Germanic element rod ‘clearing’. Compare Rhodes. This was the original home of a family de Ros, who were established in Kent in 1130.
Scottish and English: habitational name from any of various places called Ross or Roos(e), deriving the name from Welsh rhós ‘upland’ or moorland, or from a British ancestor of this word, which also had the sense ‘promontory’. This is the sense of the cognate Gaelic word ros. Known sources of the surname include Roos in Humberside (formerly in East Yorkshire) and the region of northern Scotland known as Ross. Other possible sources are Ross-on-Wye in Herefordshire, Ross in Northumbria (which is on a promontory), and Roose in Lancashire
English and German: from the Germanic personal name Rozzo, a short form of the various compound names with the first element hrōd ‘renown’, introduced into England by the Normans in the form Roce.
German and Jewish (Ashkenazic): metonymic occupational name for a breeder or keeper of horses, from Middle High German ros, German Ross ‘horse’; perhaps also a nickname for someone thought to resemble a horse or a habitational name for someone who lived at a house distinguished by the sign of a horse.
Jewish: Americanized form of Rose 3.
