the world > food and drink > farming > cultivation or tillage > breaking up land > break up land [verb (transitive)] > dig > double-dig (3)
transitive to cultivate (land) by digging parallel trenches; cf. trench, v. 3b, bastard trench, v.
transitive. To dig (ground) by digging over the lower soil with the topsoil temporarily removed. Cf. double-dig v. at double, adj.1 adv.compounds 2e.
(transitive) (see quot.); so double-digging.