The Tarf Water is a river in the former county of Wigtownshire in south-west Scotland.
It rises on the Ayrshire border (55°00′17″N 4°46′53″W / 55.0048°N 4.7815°W / 55.0048; -4.7815 (Tarf Water, source)) and flows in a generally southeastward direction to meet the River Bladnoch near the village of Kirkcowan (54°54′37″N 4°34′45″W / 54.9103°N 4.5792°W / 54.9103; -4.5792 (Tarf Water, mouth)).
It has no major tributaries but is fed by several burns that drain an area characterised by drumlins and much of which has been afforested.
[1] The name Tarf derives from the Proto-Indo-European root *tauro- 'bull, aurochs'.
[2][3] Like other examples of this name in southern Scotland, 'Tarf' is Gaelic in form but is likely to derive in turn from an earlier Cumbric cognate.