Etheridge is of Welsh origin, derived from the place name 'Eidrid', which means 'from the river Idr'. This name gained popularity due to its association with the medieval Welsh prince, Rhys ap Tewdwr, whose son was named Iorwerth ap Rhys, often referred to as 'Etheridge' in historical records. The name has since been used independently of its original location, and is considered a unique yet historically grounded choice.
The name Etheridge experienced fluctuating popularity between 1915 and 1953, with a notable spike in births from 1919 to 1920 and another peak in 1953. The total number of births over this period is 105.