Definition of "stirk"

But beware of MacPhadraick, my son; for when he called himself the friend of your father, he better loved the most worthless stirk in his herd, than he did the life-blood of MacTavish Mhor.

1827, [Walter Scott], chapter XI, in Chronicles of the Canongate; […], volume I (The Highland Widow), Edinburgh: […] [Ballantyne and Co.] for Cadell and Co.; London: Simpkin and Marshall, page 197

Comprising eleven calved and in-calf cows and heifers, three barren cows, four fat cows and heifers, two sturks and three yearlings; fifteen in-lamb ewes and theaves, […]

1843 March 3, “To Be Sold by Auction, By B. Cheatle & Son”, in Leicester Journal, and Midland Counties General Advertiser, volume 92, number 4895, Leicester: James Jackson, page 2

he could stop a running stirk by the horns, so strong he was in the wrist-bones.

1932, Lewis Grassic Gibbon, Sunset Song (A Scots Quair), Polygon, published 2006, page 20