premise: <mask> for impure, unsatisfaction for dissatisfaction, unexpressible for inexpressible, and the like
hypothesis: the best context for <mask> here is Those which are anomalous, provincial, or, for some other reason, not desirable to be used, and are so indicated; but not A trench dug in the bottom of a dry moat, and extending across it, to enable the besieged to defend it by a raking fire..