Definition of "kye"

Ay, that I do, to my cost. She and her black cat, too, live owre near my milk kye, Brindle and Hawky gi' but half the milk they should gi', and we wat weel whare the ither half gangs to.

1836, Joanna Baillie, Witchcraft, act 1

devil the move would the factor at Meikle House make to […] mend the roof of the byre that leaked like a sieve on the head of Mistress Munro when she milked the kye on a stormy night.

1932, Lewis Grassic Gibbon, Sunset Song (A Scots Quair), Polygon, published 2006, page 23

[…] wrapped in layers of warm clothing against rushing icy air, and all longing for bubbling hot kye (Navy cocoa) at midnight.

2009, John Roberts, Safeguarding the Nation: The Story of the Modern Royal Navy

Then he walked back to the wheelhouse. Guido arrived with three cups of kye and a plate of hot buttered toast.

2013, David Arnold, Hursey in Conflict: A Story of Love and Victory, page 73