Emily Dickinson Lexicon

TURF, n. [Sax. tyrf; D. turf; G. and Sw. torf; Fr. tourbe; Ir. tarp, a clod. The word seems to signify a collection, a mass, or perhaps an excrescence.]

1. That upper stratum of earth and vegetable mold, which is filled with the roots of grass and other small plants, so as to adhere and form a kind of mat. This is otherwise called sward and sod.
2. Peat; a peculiar kind of blackish, fibrous, vegetable, earthy substance, used as fuel. [Dryden and Addison wrote turfs, in the plural. But when turf or peat is cut into small pieces, the practice now is to call them turves.]
3. Race ground; or horse-racing. The honors of the turf are all our own. Cowper.