Definition of "haycock"

[T]hey perceived lying closely concealed beneath the thick foliage of a Haycock, a beautifull little Girl not more than 3 months old.

, [Jane Austen], “Henry and Eliza: a novel”, in Volume the First, page 87

And willows, willow-herb, and grass, / And meadowsweet, and haycocks dry, / No whit less still and lonely fair / Than the high cloudlets in the sky.

1917, Edward Thomas, “Adlestrop”, in Poems, London: Selwyn & Blount, page 40