Anglicization of the Irish name Dorean. It may also be a derivative of Dora with the addition of the productive suffix -een, representing an Irish pet form. It peaked in popularity in the first half of the 20th century but has since fallen from favour.
English and German: topographic name for someone who lived by the sea-shore or beside a lake, from Middle English see ‘sea’, ‘lake’ (Old English sǣ), Middle High German sē. Alternatively, the English name may denote someone who lived by a watercourse, from an Old English sēoh ‘watercourse’, ‘drain’.