Origin: Old Irish

* From Middle English Thynne, from thinne (“lean, slender”). * From Irish Ó Teimheáin, from Ó (“descendant”) + Teimheán, a name from Old Irish teimh (“dark”) + -án (diminutive suffix). * From Middle English Thynne, from þe (“the”) + in (“guesthouse, inn, hostel, house”), originating from John Boteville (1449 – p. 1485), who was called “John of the Inn” after his mansion in Stretton, Salop, to which the freehold lands of the family, with various detached copyholds, were attached.

Etymology: Wiktionary (CC-BY-SA)