Billy \b(il)-ly\ as a boy's name (also used as girl's name Billy), is a variant of Bill (English) and William (Old German), and the meaning of Billy is "will helmet, protection".

The baby name Billy sounds like Bille, Bailey, Bayly, Baley, Baily, Bell, Byll, Billie and Bly. Other similar baby names are Birly and Willy.