The surname of AVENELL was a baptismal name 'the son of Avenel'. The name was brought into England in the wake of the Norman Conquest from a small spot in France called Avenelles in the department of Eure. There are many instance of the name recorded in the Hundred Rolls of 1273, mainly documented in the Cambridge area. Early records of the name mention John Avenel, 1273 County Cambridge. Elena Avenel, County Oxford, 1273. William Averill of Yorkshire, was listed in the Yorkshire Poll Tax of 1379. Richard Treat married Mary Averill in London in the year 1626. Baptised. Ann Averill, St. James's, Clerkenwell, London in the year 1664. The name was taken early to Scotland, where the first of the name on record appears to be Robertus Avenel, who witnessed charters in the reigns of David I and William the Lion. He received from David I grants of Upper and Lower Eskdale, and was a generous benefactor to the Abbey of Melrose, bestowing on the monks of that house a large portion of his lands in Upper Eskdale. Some time after 1175, he became a humble monk in that house, and died there in 1185. For some eighty years the family was prominent in the history of Scotland. It ended in the direct line in Roger Avenel who died in 1243, and his daughter and heiress married Henry de Graham of Abercorn, into whose hands the estate passed.

The name is also spelt AVERELL and AVERILL.