- a sink is, rather unsurprisingly, used of a low-lying area of land where water collects. Such areas are often marshy and treacherous. Although originally a Scots usage, this definition is current in US English. Michael Montgomery notes a similar definition, a low-lying area or basin of land, usually having sunken ground in his Dictionary of Smoky Mountain English (2004), adding that the term also appears in place-names such as White Oak Sink in Tennessee. Until at least the late nineteenth century, the term was also used in Scots to refer to a coal-pit, or the shaft of a coal-mine. In some instances, coal-pits and boggy land go together. In A General View of the Agriculture of the Counties of Kinross and Clackmannan (1814), Patrick Graham comments on the sinks that are
small pits of eight or nine feet in diameter, and six or seven feet deep; they are to be met with frequently in this county. They are occasioned by the subsidence of the upper stratum, in fields perforated in every direction by coal-pits.