Tón
TÓN—VIII—Toan, Tone; 'son of Tona' (an Anglo-Saxon personal name, found in Domesday Book as the name of holders of land even in the time of Edward the Confessor). As a surname, it appears in Anglo-Irish records as early as the beginning of the 14th century, but has always been very rare, and is now hardly known except through Theobald Wolfe Tone.
Alphabetical Index to Irish Surnames