Auch-

Place-name element:Auch-, Auchen-, Auchin-
Dwelly Dictionary [1]Gaelic achadh ‘field, plain, meadow’

Auch-, Auchin– or Auchen- are anglicised forms of Gaelic achadh ‘field’.

Although many of these places-names now appear as names of towns (e.g. Auchinleck achadh na leac ‘field of the flat stone’) or as farms (e.g. Auchincross) they would have originally started out as field names indicative of ancillary farming activity by Gaelic speaking settlers. Place-names of this type are extremely common in the south-west of Scotland and would have been introduced from the 11th century as the former Cumbric speaking kingdom of Strathclyde lost its political identity [2].

ACKNOWLEDGEMENTS

References
[1] Edward Dwelly | Illustrated Gaelic-English Dictionary (1902-1912)
[2] W.F.H. Nicolaisen “Scottish Place-names” (1986)