v. Agric. [f. THOROUGH adv. (or sb. 3) + DRAIN v.] trans. To drain (a field) by means of water-thoroughs or -furrows; also, to drain thoroughly.
1844. Stephens, Bk. Farm, I. 489. As by this kind of draining [surface-draining] the land is thoroughly or effectually drained, it has been most appropriately called thorough-draining. Ibid., 593. A farmer … thorough-drained one-half of a 4-acre field. Ibid., 662. The subsoil will afford a sufficient quantity of stones, to thorough-drain the ground.
1847. Raynbird, in Jrnl. R. Agric. Soc., VIII. II. 311. The term thorough-draining is perhaps derived from the old word ‘thorrow,’ which Bradley mentions as ‘a distinguishing character for a trench cut purposely for carrying off of water.’
