柯林斯词典topsoil /ˈtɒpˌsɔɪl/ 1. N-UNCOUNT Topsoil is the layer of soil nearest the surface of the ground. 顶层土 返回 topsoil剑桥词典(the soil which forms ) the top layer of ground in which plants grow 表土（层） 比较subsoil 返回 topsoil