William Hay

(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.

Scottish and English: topographic name for someone who lived by an enclosure, Middle English hay(e), heye (Old English (ge)hæg, which after the Norman Conquest became confused with the related Old French term haye ‘hedge’, of Germanic origin). Alternatively, it may be a habitational name from any of various places named with this word, including Les Hays and La Haye in Normandy. The Old French and Middle English word was used in particular to denote an enclosed forest. Compare Haywood. This name was taken to Ireland (County Wexford) by the Normans.