Extance Family History
Extance Name Meaning
variant of the lost Exten with post-medieval excrescent /s/. Exten centred on Heytesbury and Bishopstrow (Wilts) a few miles north of Motcombe and east of Frome and is a variant of Exton ; compare Robert Exton 1671 in
Source: The Oxford Dictionary of Family Names in Britain and Ireland, 2016