Variant pronunciation of Thain. Compare Ralph le Theyn 1332 in Subsidy Rolls (Farley Wilts) with John le Teyn 1332 in Subsidy Rolls (Edington Wilts) and John Tane 1639 in IGI (Rowde Wilts). Some of the following bearers may alternatively belong with (3).
Possibly from Tain (Ross and Cromarty), a transferred river name based on a Celtic or pre-Celtic word denoting ‘water’ from the Indo-European root *ta- ‘flow’. It is more likely, however, that the surnames listed below are a variant pronunciation of the name in (1), the 1721 example perhaps being influenced by the place-name.
Compare Walter Thaine 1684 and Peter Thain 1694 in IGI (Rothiemay Banffs) with George Tain 1752 in IGI (Rothiemay Banffs). From Tain-L'Hermitage (Drôme), perhaps an anglicized pronunciation of Teehan from the personal name Téachán.
According to MacLysaght, Teahan ‘is almost exclusively a Kerry name’ but ‘as Tehan and Teehan it is found in Cos. Tipperary, Leix [i.e. Laois or Queen's County], and Kilkenny’. Compare the 1881 bearer from Queen's County in (3).
