Hundred in the County of Middlesex
- Helet(h)orne 1086 DB 1192 P
- Ellet(h)orne 1168,1189 P 1235 Ass
- Elet(h)orne 1169 P 1235,1274 Ass 1316,1428 FA
- Ellest(h)orne 1176 P
- Hellet(h)orne 1235 Ass
Perhaps 'Ella 's thorn tree.' This was probably, like Spelthorne supra 11, some conspicuous thorn tree or bush, but the site is not known.