a. [ L. insuperabilis: cf. OF. insuperable. See In- not, and Superable. ] Incapable of being passed over or surmounted; insurmountable;
And middle natures, how they long to join,
Yet never pass the insuperable line? Pope. [ 1913 Webster ]
The difficulty is enhanced, or is . . . insuperable. I. Taylor.
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