n. A fissure or crack: a term used by English writers in describing glaciers, to designate a rent or fissure in the ice, which may be of greater or less depth, and from an inch or two to many feet in width.n. In the United States, a breach in the embankment or levee of a river, occasioned by the pressure of water, as in the lower Mississippi.To rend, as the surface of a glacier, with fissures and cracks.