Pet form, originally Scottish, of Alexander and Alexandra. As a girl's name, particularly, it is sometimes used independently, especially in the United States. It is also used as a nickname for someone with a crop of ‘sandy’ (light reddish-brown) hair.
English: habitational name from any of various places called Belton, for example in Leicestershire, Lincolnshire, and Suffolk. The first element, bel, is of uncertain origin; the second is Old English tūn ‘enclosure’, ‘settlement’.