Dunghill (koprian). Later word in the Koiné vernacular. Here only in the N.T., though in the lxx.
Men cast it out (exō ballousin auto). Impersonal plural. This saying about salt is another of Christ’s repeated sayings (Mat 5:13; Mar 9:50). Another repeated saying is the one here about having ears to hear (Luk 8:8; Luk 14:35, Mat 11:15; Mat 13:43).